Tungurahua

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  • Ecuador
  • Ecuador
  • Stratovolcano
  • 2014 CE
  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 1.467°S
  • 78.442°W

  • 5023 m
    16475 ft

  • 352080
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

9 April-15 April 2014

IG reported that on 9 April incandescent blocks ejected by Strombolian activity at Tungurahua rolled down the flanks as far as 3 km. An ash plume rose 3 km above the crater and drifted SW, W and NW. Minor ashfall was reported in Cahuaji, Choglontus (SW), and El Manzano (8 km SW). On 10 April an emission observed during a break in cloud cover rose 500 m and drifted W. Ash fell in Quero (20 km NW), Santa Anita, Calera, and El Manzano. Later that day a lava flow on the upper W flank, in the Mandur drainage, was estimated to be 2 km long, 100 m wide, and 15 m thick. On 11 April ash plumes drifted NW, and ashfall was reported in Quero and Tisaleo. The next day ash plumes rose 3 km and drifted W. Ejected blocks from Strombolian activity traveled 1 km down the flanks. A special bulletin released by IG on 14 April reported several small to moderate explosions. A significant explosion at 0831 produced an infrasound signal that was 150 decibels 5.5 km away. Unconfirmed reports indicated that windows in Chacauco and Cusúa shattered. The shock wave was also detected in other locations including Ambato and Riobamba. An ash plume rose 5 km. On 15 April plumes with low ash content rose 3 km and drifted W. Ash fell in Runtún and Mocha. A lahar descended the Achupashal drainage, causing a temporary halt to traffic traveling on the Baños- Penipe highway.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)



 Available Weekly Reports


2014: January | February | March | April
2013: January | February | March | April | May | July | August | October | November
2012: January | February | March | April | May | June | July | August | December
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2002: January | February | March | April | May | June | July | August | September | October | November | December
2001: January | February | March | April | May | June | July | August | September | October | November | December
2000: November | December


9 April-15 April 2014

IG reported that on 9 April incandescent blocks ejected by Strombolian activity at Tungurahua rolled down the flanks as far as 3 km. An ash plume rose 3 km above the crater and drifted SW, W and NW. Minor ashfall was reported in Cahuaji, Choglontus (SW), and El Manzano (8 km SW). On 10 April an emission observed during a break in cloud cover rose 500 m and drifted W. Ash fell in Quero (20 km NW), Santa Anita, Calera, and El Manzano. Later that day a lava flow on the upper W flank, in the Mandur drainage, was estimated to be 2 km long, 100 m wide, and 15 m thick. On 11 April ash plumes drifted NW, and ashfall was reported in Quero and Tisaleo. The next day ash plumes rose 3 km and drifted W. Ejected blocks from Strombolian activity traveled 1 km down the flanks. A special bulletin released by IG on 14 April reported several small to moderate explosions. A significant explosion at 0831 produced an infrasound signal that was 150 decibels 5.5 km away. Unconfirmed reports indicated that windows in Chacauco and Cusúa shattered. The shock wave was also detected in other locations including Ambato and Riobamba. An ash plume rose 5 km. On 15 April plumes with low ash content rose 3 km and drifted W. Ash fell in Runtún and Mocha. A lahar descended the Achupashal drainage, causing a temporary halt to traffic traveling on the Baños- Penipe highway.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 April-8 April 2014

IG reported that seismicity at Tungurahua steadily increased from 2-4 April. On 2 April two small explosions, at 0757 and 2305, were accompanied by roaring and incandescent blocks rolling down the flanks. The second explosion ejected incandescent blocks and produced an ash plume that rose 600 m. Ashfall was reported in Cotaló (8 km NW) and Chacauco (NW). Although cloud cover often prevented visual observations, an ash plume generated by an explosion at 1455 on 4 April rose 2 km above the crater and drifted SW; ash fell in Choglontus (SW). On 4 April an explosion at 1810 lasted five minutes and generated pyroclastic flows that descended the NW and N flanks. An ash plume rose 10 km above the crater and drifted SW. Another explosion at 1816 lasted four minutes and possibly generated pyroclastic flows. Tephra up to 7 cm in diameter fell in Cusúa (8 km NW) and Píllaro. Constant tremor continued, interspersed with explosions. Strombolian activity was observed during the morning of 5 April. Steam-and-gas emissions with small amounts of ash rose less than 1 km and drifted W. At 1040 an ash plume rose 2 km. On 6 April ash plumes drifted W, and Strombolian activity ejected material that was deposited 1.5 km down the flanks. Ashfall was reported on 7 April in Bilbao (W) and Cevallos (23 km NW). On 8 April steam emissions with some ash rose 200 m and drifted SW. Minor ashfall was reported in Bilbao, El Manzano (8 km SW), Juive (7 km NNW), Mocha (25 km WNW), El Manzano. Large lahars descended the Achupashal (NW) and Confesionario drainages (WSW).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 March-1 April 2014

IG reported that cloud cover occasionally prevented observations of Tungurahua during 26 March-1 April, although on clear days no surface activity was observed. Minor ashfall was reported in El Manzano (8 km SW) and Cahuaji on 26 March. Seismicity was at moderate levels and then declined during 28 March-1 April. Lahars on 31 March traveled down the Vascún (N) and Mapayacu (SW) drainages, carrying blocks up to 1 m in diameter in the latter drainage.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 March-25 March 2014

IG reported that activity at Tungurahua was at moderate levels during 19-25 March; cloud cover often prevented observations. On 21 March an explosion was later followed by ashfall in Choglontus (SW). Heavy rains caused lahars in the Achupashal drainage (NW) which led to traffic disruption on the Baños- Penipe highway. Lahars also descended the Juive drainage (7 km NNW). On 25 March an ash plume rose 3 km and drifted N. Ashfall was reported in Quero (20 km NW) and Puñachiza.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 March-18 March 2014

IG reported that activity at Tungurahua was at moderate levels during 11-16 March, but then declined during 17-18 March; cloud cover occasionally prevented observations. On 11 March rain caused major lahars in the Achupashal drainage which led to traffic disruption on the Baños- Penipe highway. Ash plumes on 12 March rose 1 km above the crater. On 14 March ash plumes rose 3 km and drifted W and SE. Sounds resembling blocks rolling down the flanks were reported by residents in Runtún (6 km NNE).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


5 March-11 March 2014

IG reported that activity at Tungurahua was at moderate levels during 5-11 March; cloud cover occasionally prevented observations. Two explosions during 5-6 March were felt in local areas, and at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). Ashfall was reported in El Manzano (8 km SW) and Palictahua. An explosion on 6 March generated an ash plume that rose 2 km and drifted NE. On 8 March ash plumes rose as high as 2 km and drifted W and NW. The next day an ash plume rose 1 km and drifted NE; ashfall was reported in Minsa.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 February-4 March 2014

IG reported that activity at Tungurahua was at moderate levels during 26 February-4 March; cloud cover often prevented observations. On 26 February a small pyroclastic flow traveled 400 m down the N and NW flanks. Ashfall was reported in El Manzano (8 km SW) and Palictahua. The next day seismicity increased and inflation was detected at the summit area. Diffuse vapor plumes rose from the crater during 1-2 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 February-25 February 2014

IG reported that activity at Tungurahua was at moderate-to-high levels during 19-25 February; cloud cover often prevented observations. On 20 February ash plumes rose 2-3.5 km above the crater and drifted SW. Ashfall was reported in Píllate (8 km W), Quero (20 km NW), and Tizaleo (29 km NW). The next day observers reported blocks rolling down the flanks. Ash fell in Píllate on 23 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 February-18 February 2014

IG reported that on 11 February explosions from Tungurahua generated ash plumes that rose 3 km above the crater and drifted WNW. Roaring noises and sounds resembling blocks rolling down the flanks were noted. A small pyroclastic flow traveled down the flanks at 1720, and ashfall was reported in El Manzano (8 km SW). Incandescence on the N flank was observed at night during 12-13 February. Ash plumes again rose 3 km on 13 February causing ashfall in Choglontus (SW) and Capil. During 13-14 February Strombolian activity ejected blocks that rolled 500 m down the N flank. Ash plumes rose 3 km and drifted W, and minor amounts of ash fell in Tisaleo (29 km NW). Cloud cover prevented views on 15 February; ashfall was reported in Penipe (15 km SW). During periods of clear weather on 16 February observers noted that ash plumes rose 3 km. Ash fell in Runtún (6 km NNE), Penipe, and El Manzano. At night during 16-17 February incandescence from the crater was observed along with blocks that rolled 500 m down the flanks. Gas-and-ash plumes rose 5 km and drifted N, NW, W and SW, and ashfall was reported in Penipe, Chacauco (NW), and Pillate (8 km W). An ash plume rose 4 km on 18 February and drifted W. Minor amounts of ash fell in Choglontus.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


5 February-11 February 2014

On 6 February, IG reported that since 3 February Tungurahua had produced almost constant emissions of gas, steam, and ash that rose 3-4 km above the crater and drifted N, causing ashfall in Ambato (31 km N), Patate (NW), Latacunga, and parts of Quito (130 km N). During 5-6 February ash plumes drifted E and SE and caused ashfall in Pondoa (8 km N), Vazcún (N), Runtún (6 km NNE), and San Antonio, and to a lesser extent in Rio Verde and Rio Negro. Strombolian activity was observed on 6 February.

Cloud cover often prevented visual observations during 7-11 February; explosions continued to be detected, roaring was periodically heard, and sounds resembling rolling blocks were occasionally reported. On 7 February ash fell in Palictahua. The next day a gas-and-ash plume rose 500 m and drifted W and SW. On 9 February an ash plume rose 4 km and drifted NW and NE. Strombolian activity ejected blocks 1 km away. During 10-11 February explosions vibrated structures, and ashfall was reported in Quero (20 km NW), Mocha (25 km WNW), El Manzano (8 km SW), and Choglontus (SW).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 January-4 February 2014

IG reported that during the morning of 30 January the seismic network recorded an increase in the number of events at Tungurahua including some low-magnitude explosions, long-period events, and seismic tremor. Ashfall was reported in Pungal (40 km SSW), Penipe (15 km SW), and Palictahua in the district of Penipe. Cloud cover prevented ground observations, but IG noted that satellite images indicated the presence of ash plumes and thermal anomalies. The number and size of explosions increased at night during 30-31 January, and then a sharp decline in activity was noted on 31 January, characterized by very low seismicity. At 1701 an explosion generated an ash plume that rose 2 km and drifted SE and SW.

On 1 February, between 0800 and 1700, a swarm of volcano-tectonic earthquakes occurred in the upper conduit. Two moderately-sized explosions, at 1712 and 1732, generated ash plumes that rose 5 km, and pyroclastic flows that traveled 500 m down the NE and NW flanks. A larger explosion at 1739 produced an ash plume that rose 8 km and drifted SE and possibly SSE. Based on reports from IG, satellite images, pilot observations, web-camera images, and the Guayaquil MWO, the Washington VAAC reported that the ash plume rose to an estimated altitude of 13.7 km (45,000 ft) a.s.l., and drifted S at high altitudes and SW at lower altitudes. IG noted that pyroclastic flows traveled 7-8 km, reaching the base of the volcano and traveling over the Achupashal Baños- Penipe highway. Continuous ash-and-gas emissions followed; ash fell in multiple areas and total darkness was reported in Chacauco (NW). Explosions occurred every minute and vibrated structures in local towns. Pyroclastic flows descended the SW, W, NW, and NE flanks, and stopped short of towns and infrastructure. Ash emissions were sustained through the rest of the evening, and Strombolian explosions ejected incandescent blocks 800 m above the crater that fell and rolled 500 m down the flanks.

Activity gradually declined at 1900 until 2100 when explosions became more sporadic. On 2 February explosions at 0659, 0723, and 0801 were followed by ash emissions. During 2-3 February at least 10 explosions occurred and were heard in areas several kilometers away. On 3 February an ash plume rose 4 km and drifted N, reaching Quito as a mist of suspended very fine material that lingered most of the day.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Prensa Latina


6 November-12 November 2013

IG reported that activity at Tungurahua remained at moderate levels during 6-12 November. Although cloud cover sometimes prevented visual observations of the crater, ash plumes were observed on most days. An ash plume rose 1 km and drifted W on 7 November. The next day ashfall was reported in Runtún (6 km NNE), Pondoa (8 km N), and Baños (8 km N). On 9 November an ash plume rose 3 km and drifted W, and blocks rolled down the flanks. Ash fell in Choglontus (SW), Bilbao (W), and Cusúa (8 km NW). On 10 and 12 November ash plumes rose 1 km and drifted SW, and 1.5 km and drifted W, respectively. Ashfall was reported in El Manzano (8 km SW) on 12 November.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 October-5 November 2013

IG reported that, during the last week of October and the first days of November, moderate activity continued at Tungurahua; there were ~10 explosive emissions recorded. Plumes reached 800-2,000 m above the crater and drifted E and SE; ashfall was not reported from nearby communities. Seismicity included explosions, long-period earthquakes, volcano-tectonic earthquakes, and tremor (often associated with emissions). SO2 flux measured during this time period reached a maximum of 725 tons per day. Inflation and deflation trends continued to be detected by the tiltmeter network. Since August 2012 there have been six periods of general deflation each separated by 2-3 month intervals of relative stability.

Ongoing emissions were reported by the Washington VAAC on 30 October, primarily due to elevated seismicity. On 3 November, a pilot observed an ash plume at 8.5 km a.s.l. (28,000 ft); later in the day, ash was detected by the GOES-13 weather satellite as well as the local weather observatory and pilots. The ash plume reached 6.7 km a.s.l. (22,000 ft) and extended ~28 km SE.

During the evening of 4 November, IG observed an ash plume rising from the crater up to ~1 km a.s.l. and drifting SE. Cloudy conditions restricted observations on 5 November.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


23 October-29 October 2013

IG reported that activity at Tungurahua remained high during 23-27 October. Although cloud cover sometimes prevented visual observations of the crater, ash plumes were observed almost daily. During 23-24 October continuous ash emissions produced plumes that rose 3-4 km above the crater and drifted NNE and SW. Ashfall was reported in Penipe (15 km SW), Palitahua (S), Riobamba (30 km S), Tisaleo (29 km NW), El Manzano (8 km SW), and Choglontus (SW). On 25 October blocks were observed rolling down the flanks, and ash fell in El Manzano and Choglontus. The next day continuous ash emissions rose 2 km and drifted SW. Ashfall was noted in Cevallos (23 km NW), Mocha (25 km WNW), Tisaleo, Penipe, El Manzano, and Cloglontus. Ash plumes rose 2 km and drifted W on 27 October. Low-energy gas-and-ash emissions drifted W and SW on 28 October. Ashfall was reported in Palitahua. On 29 October ash plumes rose 4 km and drifted E and NE. Ash fell in Penipe, Mocha, and El Manzano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 October-22 October 2013

IG reported that after a 3-month lull in activity at Tungurahua, a new eruption that began on 6 October was characterized by increased seismicity, Strombolian activity that ejected incandescent blocks, and ash plumes that produced ashfall in nearby areas. Seismicity peaked on 11 October and high-level ash plumes again produced ashfall in nearby towns. The number of explosions increased on 14 October and two small pyroclastic flows traveled a few hundred meters the next day.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 August-13 August 2013

IG reported that seismic activity at Tungurahua was moderate to high during 7-13 August; the seismic network detected long-period earthquakes indicating fluid movement and some emissions. Although cloud cover mostly prevented visual observations of the crater, plumes were occasionally observed. On 8 August an ash plume rose 2 km and drifted W, and ash fell in Choglontus (SW). A small steam plume rose 100 m and drifted SW the next day. Minor vapor emissions were noted on 11 and 13 August.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


31 July-6 August 2013

IG reported that activity at Tungurahua remained high during 31 July-5 August; the seismic network detected explosions, emissions, and long-period earthquakes indicating fluid movement. Although cloud cover mostly prevented visual observations of the crater, plumes were occasionally observed. Roaring was also heard. Steam plumes with low ash content were observed on 31 July, and on 1 August drifting W. Ashfall was reported in Mocha (25 km WNW) on 31 July and in El Manzano (8 km SW) on 1 August. On 2 August a low-energy steam-and-ash emission was noted. During 2-3 August ash fell in El Manzano and Choglontus (SW).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 July-30 July 2013

IG reported that activity at Tungurahua remained high during 24-30 July. Although cloud cover often prevented visual observations of the crater, plumes were observed almost daily. Roaring was also regularly reported. On 24 July an ash plume rose 5 km above the crater and drifted WNW, causing black ashfall in El Manzano (8 km SW), Choglontus (SW), Puela (8 km SW), Cahuají (8 km SW), and minor ashfall in Cevallos (23 km NW), Quero (20 km NW), and Mocha (25 km WNW). On 25 July ashfall was reported in El Manzano, Choglontus, and Cahuají. An explosion at 1835 generated an ash plume that rose 2 km and drifted W. The next day windows vibrated at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). Minor amounts of ash fell in El Manzano, Choglontus, Puela, Mocha, and in the sectors of Guaranda (65 km WSW), Salinas, and Guanujo (65 km WSW). Overnight during 26-27 July Strombolian activity ejected blocks that rolled 300 m down the flanks. At 1947 a strong explosion vibrated windows at OVT and in El Manzano and Pillate (8 km W). An ash plume rose 2 km and drifted WSW; minor ashfall was reported in Bilbao (W), Quero, and Mocha. Later that day ash emissions rose 500 m and drifted SW.

Activity increased on 28 July; at 0626 a higher number of long-period earthquakes were detected, explosions became more frequent and larger, blocks were ejected, and ash emission rose from the crater. An explosion at 0723 generated a small pyroclastic flow that descended the N flank. Ash fell in Choglontus, El Manzano, Mocha, and Tisaleo (29 km NW). Activity remained high the next day; ash plumes rose 2 km and drifted WNW. During 28-29 July and ashfall was reported in Mocha, Quero, Tisaleo, Cevallos, and Pillate.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 July-23 July 2013

IG reported that at night during 16-17 July observers noted incandescent blocks falling onto Tungurahua's flanks. Cloud cover often prevented observations. An explosion was heard in Ambato (31 km N) on 16 July. Explosions were detected on 17 July, and white ashfall was reported in Choglontus (SW). Steam-and-ash plumes were observed rising 1.5 km and drifting W. During 18-19 July Strombolian activity ejected blocks that rolled 500 m down the flanks. Ash fell in Choglontus. Seismicity remained high during 17-19 July; 18-33 long-period earthquakes, 53-82 tremors indicting emissions, and 3-6 explosions were recorded per day.

On 19 July an ash plume rose 1 km and drifted SW. The geodetic monitoring system indicated an inflationary trend on the N flank and deflation SW of the volcano, indicating the presence of a magma body about 2 km below the crater. During 19-20 July ashfall was reported in Choglontus and El Manzano (8 km SW). On 20 July 127 long-period earthquakes, 71 tremors indicting emissions, and 43 explosions were detected.

Seismicity again increased on 21 July; 220 long-period earthquakes, three periods of tremor indicating emissions, and 15 explosions were detected. The three periods of tremor were characterized by two 1-hour-long sessions and a third period lasting at least eight hours. Explosions vibrated nearby structures, and ejected blocks onto the upper parts of the flanks. Gas-and-ash plumes rose as high as 5 km, and produced ashfall in Cevallos (23 km NW), Tisaleo (29 km NW), Mapayacu (SW), Choglontus, and El Manzano. Strombolian activity overnight during 21-22 July ejected blocks that rolled 500 m down the flanks. Strong explosions again vibrated structures, and ash emissions rose 1 km. Ashfall was noted in El Manzano, Pillate, Chacuaco and Cahuaji. On 23 July ash plumes rose 1.5 km and drifted WSW. Strombolian activity was observed overnight and roaring was heard. Ashfall was reported in Cahuají and Choglontus. Seimscity decreased but still remained high during 22-23 July; 22-40 long-period earthquakes, 7-12 tremors indicting emissions, and 4-9 explosions were detected per day.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 July-16 July 2013

IG reported that seismic activity at Tungurahua was at low levels during 10-11 July, increased to moderate levels on 12 July, and increased again to moderate-to-high levels on 13 July; the number and type of events gradually and constantly increased. Cloud cover prevented visual observations of the crater. A total of 266 long-period events were recorded from 1500 on 13 July through the time of a large explosion at 0647 on 14 July, which was heard in areas as far as Guayaquil (about 180 km SW).

At 0651 an ash plume generated by the explosion rose 5.1 km above the crater and several significant pyroclastic flows descended the Achupashal ravine (NW). Continuous tremor was detected until 0840, and then seismicity dramatically decreased. At 0842 the plume rose to 8.3 km above the crater and drifted N, W, and S. At 0930 the plume drifted N and was observed drifting over the E parts of Quito (130 km N). Heavy amounts of ash and tephra fell in areas near the volcano including Bilbao (W, 4 cm diameter), Chacauco (NW, 5 cm diameter), Cotaló (8 km NW), Cahuají (8 km SW), Choglontus (SW), El Manzano (8 km SW), Puela (8 km SW), and Penipe (15 km SW); thinner deposits were reported in towns including Pelileo (8 km N), Ambato (31 km N), Cevallos (23 km NW), Colta (45 km SW), Guanujo (65 km WSW), and Guaranda (65 km WSW), and in the cantons of Guano (30 km SW), Valencia, Empalme, Buena Fé, and areas in the province of Manabi (180 km NW). According to news articles, over 200 people were evacuated from Cusua, Chacauco, and Juive.

On 15 July steam plumes were observed rising from the crater during times of better visibility. Long-period earthquakes and tremor were detected during 15-16 July. Ashfall was reported in El Manzano on 16 July; cloud cover continued to prevent observations of the crater.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Associated Press


15 May-21 May 2013

IG reported that during 15-20 May seismicity at Tungurahua remained at a moderate level and then decreased on 21 May. Visual observations were often limited due to cloud cover; steam plumes were observed rising from the crater on 17 and 19 May. A slight amount of ash fell in Choglontus (SW) on 15 May, and small lahars traveled down the Bilbao (W), Pingullo (NW), and La Pampa (S) on 20 May.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 May-14 May 2013

IG reported that although cloud cover often prevented observations of Tungurahua during 8-14 May, ash plumes were observed almost daily. Seismicity remained at a moderate level. Explosions occasionally vibrated structures nearby and at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). Strombolian activity was observed on most nights ejecting blocks sometimes 500 m above the crater; blocks that fell onto the flanks rolled as far as 1 km. During 9-10 May lava fountains rose 700 m above the crater. During 8-11 May ash plumes rose 1-2.5 km and drifted SW, W, and NW, producing ashfall in El Manzano (8 km SW), Choglontus (SW), Quero (20 km NW), Mocha (25 km WNW), Pillate (8 km W), Tisaleo (29 km NW), and Penipe on 8 and 10 May, and in Santa Fe de Galán, Mocha, Sabañag (15 km WNW), Tisaleo, and Quero (20 km NW) on 11 May. Ashfall was reported in Quero on 12 May. The next day explosions generated ash plumes that rose 2-3 km and drifted NW and W, producing ashfall in El Manzano. Roaring and sounds resembling rolling blocks were reported. On 14 May ash fell in Choglontus, El Manzano, and Mocha.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 May-7 May 2013

IG reported that although cloud cover often prevented observations of Tungurahua during 1-7 May ash plumes were observed almost daily. Seismicity remained at a moderate level, although it increased on 4 May.

On 1 May an explosion and rolling blocks were heard, and ashfall was reported in El Manzano (8 km SW). The next day steam-and-ash plumes rose 1-1.5 km above the crater and drifted W. Ashfall was reported in Cevallos (23 km NW), Tisaleo (29 km NW), Quero (20 km NW), and Mocha (25 km WNW). During 2-4 May Strombolian activity was observed at night. On 3 May several explosions produced ash plumes that rose 2-3 km above the crater and drifted N and NW. Ash fell in Juive (7 km NNW), Runtún (6 km NNE), Pondoa 8 km N), Baños (8 km N), Patate (NW), Pelileo (8 km N), Ambato (31 km NW), Cevallos, and at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). On 4 May explosions rattled windows in Baños, and ash plumes rose 1-1.5 km and drifted N and NW. Large lahars traveled down the La Pampa drainage on the S flank, while other lahars traveled down the Vazcún, Juive, and Mandur drainages on the N and NW flanks. Explosions on 5 May rattled windows in Ventanas, Pondoa, and Runtún. An ash plume rose 2 km and drifted W. Ashfall was again reported in Cevallos, Tisaleo, Quero, and Mocha. A pyroclastic flow descended the NW flank 2 km. On 6 May ash plumes drifted SW and ashfall was reported in Cevallos, Tisaleo, Quero, Mocha, Pillate (8 km W), Choglontus (SW), and El Manzano. The next day ash plumes rose 3 km and drifted SW. Ashfall was reported in Sabañag (15 km WNW), Chazo, Ilapo, and Riobamba (30 km S).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 April-30 April 2013

IG reported that during 24-26 April activity at Tungurahua was low. On 27 April seismic activity increased; an ash plume rose 2 km above the crater and drifted NW, causing ashfall in Juive (7 km NNW). During the morning on 28 April steam-and-ash plumes rose 1-4 km and drifted at least 100 km SW and W. Later that day several explosions produced ash plumes that rose as high as 3.5 km and drifted W. Ashfall was reported in Baños (8 km N), Chacauco (NW), Bilbao (8 km W), Cusúa (8 km NW), Juive, Pondoa (8 km N), and Pillate (8 km W). At 1830 a steam-and-ash plume rose 5 km, and drifted SW and then W. Another explosion ejected incandescent blocks that fell on the flanks 400 m below the crater. During breaks in cloud cover on 29 April dark gray emissions were observed drifting ESE. Ashfall was reported in El Manzano (8 km SW), Cahuají (8 km SW), Puela (8 km SW), Penipe (15 km SW), and Riobamba (30 km S). An explosion caused structures to vibrate. On 30 April explosions produced ash plumes that rose 1.5-2 km and drifted WSW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 March-2 April 2013

IG reported that during 27 March-2 April seismicity at Tungurahua continued to trend downward, remaining at moderate levels. Cloud cover often prevented observations; a weak steam plume was observed rising from the crater on 27 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 March-26 March 2013

IG reported that during 18-20 March seismicity at Tungurahua was high. Although cloud cover often prevented observations, steam-and-ash plumes were observed rising as high as 1 km above the crater. Slight ashfall was reported in Riobamba (30 km S) on 18 March. Seismicity declined on 21 March and continued to trend downward during 22-26 March. A small lahar descended the Chontapamba drainage (W) on 21 March. Steam plumes drifted W on 22 March, and were again observed during 25-26 March. A plume with low ash content rose 1 km above the crater on 24 March and drifted N. Slight roaring was reported from El Manzano (8 km SW).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 March-19 March 2013

IG reported that during 13-17 March seismicity at Tungurahua was high. On 13 March ash plumes rose 1-3 km above the crater, and generated ashfall in Choglontús (SW) and Puela (8 km SW). The next day nearly continuous emissions of gas and ash rose 500 m. Explosions produced ash plumes that rose 3 km; ash fell between the Mapayacu (SW) and Rea drainages, and in Choglontús, Cahuají (8 km SW), and El Manzano (8 km SW). Blocks rolled 500 m down the flanks. On 15 March ash plumes drifted SE and W. An explosion generated an ash plume that rose 4 km and drifted E. A pyroclastic flow occurred near the crater. Explosions on 16 March generated ash plumes; ashfall was reported in Puela, Pillate (8 km W), and Ambato (31 km NW). On 17 March explosions again produced ash plumes that rose 4 km. Lava fountains rose 200-300 m above the crater and incandescent material fell on the flanks. A pyroclastic flow descended the upper parts of the Mandur (NW) drainage. Ashfall was reported in El Manzano, Palictagua and Choglontús.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 March-12 March 2013

IG reported that during 2-12 March seismicity and sulfur dioxide emissions at Tungurahua were both moderate to high. Over 100 earthquakes were detected daily; 157 high-frequency tremors were recorded on 3 March and 233 long-period events were recorded on 6 March. Deformation measurements indicated that the rising magma body was small and concentrated beneath the NW flank.

Although cloud cover often prevented visual observations during 6-12 March, ash emissions were observed almost daily. On 6 March a steam plume with low ash content rose 1.5 km above the crater. Roaring was heard at night during 6-7 March, and ashfall was reported in Palitahua (S), El Manzano (8 km SW), Penipe (15 km SW), and Choglountus (SW). Ash plumes rose 1 km above the crater on 7 March and 2 km the next day, drifting W. During 8-12 March Strombolian activity ejected incandescent blocks that rolled at most 500 m down the flanks. Ash plumes drifted S, SW, and W. Ashfall during 10-11 March was reported in El Manzano and Choglountus. On 11 March ashfall was also reported in Pillate (8 km W).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 February-5 March 2013

IG reported that seismicity at Tungurahua increased on 28 February. The next day an increase in the number of long-period earthquakes was accompanied by small explosions, roaring, and ash emissions. At around 1600 on 1 March a plume of water vapor and gas containing small amounts of ash rose a few hundred meters above the crater and drifted WNW. Ashfall was reported in areas on the SW flank including Choglontús (SW) and Manzano (8 km SW). On 2 March an explosion at 1106 produced noises from blocks rolling down the flanks. Instruments detected deformation on the NW flank. Cloud cover during 1-2 March inhibited visual observations.

At night during 2-3 March incandescent blocks were ejected from the crater and rolled 300 m down the flanks. Seismicity again increased on 3 March. Ash plumes rose from the crater and produced ashfall in Manzano and Penipe (15 km SW). Cloud cover prevented views on 4 March, however ashfall was reported in Manzano. On 5 March explosions produced an ash plume that rose 1-1.5 km above the crater and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 January-8 January 2013

On 3 January, IG reported that since 31 December seismicity at Tungurahua had decreased, and during 2-3 and 7-8 January there were no explosions, noises, or reported ashfall. One small explosion was detected on both 4 and 5 January. An explosion on 6 January was accompanied by roaring and sounds of rolling blocks. Minor ashfall was reported in Manzano (8 km SW). Cloud cover had often prevented visual observations during 31 December-8 January.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 December-25 December 2012

IG reported that during 19-25 activity at Tungurahua remained high. On 19 December there were 60 explosions detected by the seismic network; explosions vibrated structures and were often heard by local residents. Ash plumes rose 2 km above the crater and drifted SW, causing ashfall in communities downwind including Choglontús (SW), Manzano (8 km SW), Palitahua (S), and Puela (8 km SW). The next day 78 explosions were detected, roaring was heard, and windows vibrated. Ash plumes rose 1 km and drifted W and SW. Ashfall was reported in Manzano, Palitahua, Choglontús. A pyroclastic flow, generated after an explosion, traveled 2 km down drainages on the NW flank.

During 21-25 December explosions ejected incandescent blocks that rolled as far as 1 km down the flanks. Gas-and-ash plumes rose less than 2 km above the crater and drifted W and NW. On 22 December ashfall was reported in Pillate and Manzano, and lava fountains 500 m high were observed at night. On 23 December explosions rattled windows. Strombolian explosions ejected incandescent blocks more than 500 m above the crater that rolled 1 km down the W and NW flanks. The next day seismicity decreased and minor ashfall Choglontús in was reported.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 December-18 December 2012

IG reported that on 1 December there was 47 mm of rainfall on the upper E and NE flanks of Tungurahua, generating lahars that descended the Vazcún drainage on the N flank. Seismic stations began recording signals representing the lahars at 1556, and by 1605 contingency plans were activated to warn people downstream. People at the resort of El Salado had been evacuated by the time the lahars reached the area. The lahar was 6 m deep, carried blocks 1-3 m in diameter, and covered drinking water tanks in some areas.

Seismicity at Tungurahua reported by IG increased during 12-14 December. A large explosion at 1435 on 14 December produced a "cannon shot" sound and shook the ground. An ash-and-steam plume rose 6-7 km and drifted NW. Pyroclastic flows traveled down the SW flank. The Washington VAAC reported that an 11-km-wide detached ash plume was observed in satellite imagery drifting 17 km SE. On 15 December IG reported that an explosion was followed by an ash-and-gas plume that rose 2 km above the crater and drifted S and SE. Small amounts of ash fell in Runtún (6 km NNE).

On 16 December a large explosion generated ash plumes that rose to a maximum height of 7 km and contained lightning. Other explosions generated ash plumes that rose 2 km. Satellite imagery showed ash plumes drifting 140 km NW, and 110 km NE at an altitude of 7.9 km (26,000 ft) a.s.l. Tephra fell in Cotaló (8 km NW), Pondoa (8 km N), Runtún, and Pillate (8 km W), and coarse ash fell in Baños (8 km N), Vascún, and Ulba (NNE). Medium-to-fine-grained ash fell in Palitahua (S), Choglontús (SW), Manzano (8 km SW), Capil, Guadalupe Observatory (11 km N), Cevallos (23 km NW), Tisaleo (29 km NW), Ambato (31 km NW), Patate (NW), Píllaro, Pelileo (8 km N), Salcedo, and Pujilí Latacunga, Rio Verde, Agoyán, and Palora. The larger explosions during the morning produced "cannon shots" that broke a window in a local building, and were followed by pyroclastic flows that descended the SW and NW flanks. During 16-17 December incandescent blocks were ejected from the crater and rolled down the flanks.

On 17 December satellite images showed ash plumes drifting 50-130 km NE, and a dense ash plume drifting over 200 km NE at an altitude of 7 km (23,000 ft) a.s.l. A thermal anomaly was also detected. IG noted that explosions continued to generate ash plumes, but with progressively decreasing ash content. Ash plumes drifted NNE and NE, causing ashfall in communities downwind. According to a news article, some of these communities were evacuated.

The VAAC noted that a thermal anomaly was detected on 18 December. Ash plumes drifted 70 km W and 40 km SW. IG reported that seismicity remained elevated, and two pyroclastic flows traveled at most 3-4 km down the flanks and burned vegetation. Explosions rattled structures and ejected incandescent blocks. Ash plumes rose 2-3 km above the crater and drifted NW, W, and SW. Ash fell in multiple areas, and accumulated between 1 and 2 mm during 17-18 December in Juive (7 km NNW).

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), ABC News - American Broadcasting Corporation


29 August-4 September 2012

IG reported that during 29 August-4 September visual observations of Tungurahua were often limited due to cloud cover. Moderate seismicity was detected during 29-30 August and a few earthquakes were felt by residents. On 30 August steam plumes with low ash content rose 500 m above the crater and drifted W. Ashfall was reported in Manzano (8 km SW) and Choglontus. Incandescent blocks rolled 300 m down the flanks, roaring was heard, and structures in nearby areas vibrated. During 31 Auguts-1 September steam plumes rose 300-500 m and drifted W. Glow emanated from the crater and incandescent blocks rolled down the flanks, up to 500 m on 31 August. Ashfall was reported in Manzano. An explosion produced a plume that rose 300 m on 3 September, and a steam plume drifted W on 4 September.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 August-28 August 2012

IG reported that at about noon on 21 August Tungurahua entered a second stage of activity since the onset of the eruption that began early in August. The second stage was characterized by low-to-moderate levels of activity; emissions decreased and intense seismic tremor declined to sporadic episodes lasting only a few minutes. During 22-28 August visual observations were often limited due to cloud cover. On 22 August steam-and-gas plumes rose from the crater, roaring was heard, and ashfall was reported in Choglontús (SW). Explosions at night ejected incandescent tephra that landed on the flanks 500 m below the crater. The next day gas-and-ash plumes rose 1.5-4 km above the crater and drifted W and NW. Ashfall was reported in Choglontús, Pillate (7 km W), and El Tablón. On 24 August gas-and-ash plumes rose 2 km and drifted W. During 24-25 August ash fell in Manzano (8 km SW), Choglontus, Chacauco (NW), Bilbao (8 km W), and Pillate. Explosions on 26 August generated ash-and-gas plumes that rose 2-3 km and drifted NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 August-21 August 2012

IG reported that on 15 August three small explosions from Tungurahua were detected along with continuous tremor. An ash plume rose 1 km above the crater and drifted W, producing ashfall in El Manzano (8 km SW) and Pillate (7 km W). Activity increased the next day, characterized by increased tremor, roaring sounds, and instances of vibrating windows. An ash plume again rose 1 km, drifted W, and produced ashfall in El Manzano and Pillate. On 17 August two long periods of tremor associated with emissions were detected; 10 explosions were also recorded. Periodic clear views of the crater showed continuous steam-and-ash plumes rising 1.5-3 km above the crater and drifting WNW. Ash fell in Pillate and Bilbao (8 km W). Activity significantly increased at 2100, and strong explosions were detected. Cloud cover prevented visual observations.

In the morning of 18 August, satellite images showed a 50-km-long plume drifting NW. A pyroclastic flow deposit on the NW flank was observed with a thermal camera. Steam-and-ash plumes rose 1.5 km and drifted WNW; ashfall was reported in Choglontús (SW), Pillate, and San Juan de Pillate (9 km W). Strong glow from the crater was observed at night, along with incandescent blocks rolling down the top of the cone. A pyroclastic flow descended the NE flank, and a lava flow on the N flank traveled 500 m.

Activity remained elevated on 19 and 20 August; continuous tremor indicating emissions was detected, along with nine explosions on 19 August and five on 20 August. Steam-and-ash plumes rose 1.5-2 km and drifted W and SW. Ash fell in Pillate, Igualata (20 km W), El Santuario, Hualpamba, Cevallos (23 km NW), Quero (20 km NW), Mocha (25 km WNW), Santa Anita, and Tisaleo (29 km NW). Roaring sounds were heard and explosions vibrated windows. Strombolian activity ejected incandescent blocks that landed a few hundred meters away. An overflight on 20 August revealed an 80-m-wide inner crater that contained lava. Blocks had accumulated at the headwaters of streams on the SW, W, and NW flanks. According to a news article, 110 families were evacuated.

On 21 August 16 large explosions were detected and again caused windows to vibrate. Strong "cannon shots" were heard in areas as far as Ambato (40 km NW), Riobamba (30 km S), and Milagro, though roaring noises decreased in intensity and duration compared to the previous few days. Ash plumes rose 1.5-5 km and drifted W, and a pyroclastic flow traveled 2.5 km down the NW flank.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Associated Press


8 August-14 August 2012

IG reported that during 8-13 August visual observations of Tungurahua were limited due to cloud cover. A vapor emission drifted W on 8 August. A small explosion on 10 August vibrated windows, and ash fell in Choglontús (SW). Three to four explosions on 11 and 12 August produced "gun shot" noises. At night incandescence from the crater was observed and sounds resembling blocks rolling down the flanks were reported. On 11 August an ash-and-steam plume rose from the crater, and the next day an ash plume rose 1 km and drifted W. During 12-13 August incandescent blocks were ejected 100 m above the crater and rolled 500 m down the flanks. Roaring was heard and ash fell in Cusúa (8 km NW) and Juive (7 km NNW). On 14 August seismicity increased and was accompanied by increased emissions. Ashfall was reported in Pillate (7 km W), Cusúa, and Choglontús.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 August-7 August 2012

IG reported that during 1-5 August visual observations of Tungurahua were limited due to cloud cover. A small steam plume rose from the crater on 3 August and drifted W. Explosions on 5 August vibrated windows in nearby areas and produced sounds resembling gunshots. A plume rose 3 km above the crater and drifted W. Explosions during 5-6 August produced gas plumes with small amounts of ash that drifted WSW. Steam plumes rose 100 m above the crater the next day.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 July-31 July 2012

IG reported that during 25-31 July visual observations of Tungurahua were limited due to cloud cover. On 25 July incandescence from the crater was observed at night, an explosion generated a "cannon shot" noise, and there were sounds resembling blocks rolling down the flanks. The next day a steam plume rose 200 m above the crater and drifted W. The Juive (NNW), La Pampa (S), and Mapayacu (SW) drainages contained muddy waters on 29 July; water on the Mapayacu drainage carried blocks that were 50 cm in diameter. An explosion on 30 July produced sounds resembling rolling blocks and caused vibrating windows in surrounding areas. One small explosion was detected on 31 July.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 July-24 July 2012

IG reported that during 18-24 July visual observations of Tungurahua were limited due to cloud cover. On 20 July a steam plume drifted W, and on 21 July a steam plume rose 200 m above the crater and drifted the same direction. Many of the drainages contained muddy waters through the reporting period; a lahar descended the Mapayacu drainage (SW) on 23 July.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 July-17 July 2012

IG reported that during 10-12 July explosions from Tungurahua were detected by the seismic network. On 11 July a gas-and-ash plume rose 1 km above the crater and drifted W. Residents reported "cannon shot" sounds, along with sounds resembling blocks rolling down the flanks. Slight ashfall was reported in Bilbao (8 km W). On 12 July gas-and-steam plumes rose 0.3-1 km high and an ash plume rose 1.5 km high. Cloud cover often prevented observations of the volcano during 13-16 July; clear views on the morning of 15 July showed no activity at the crater. A small explosion was detected on 14 July and an explosion on 17 July generated a steam plume with low ash content.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 July-10 July 2012

IG reported that during 4-10 July visual observations of Tungurahua were limited due to cloud cover. An explosion on 5 July produced "cannon shot" sounds, along with sounds resembling blocks rolling down the flanks. Ashfall was reported in Manzano (8 km SW) and Chacuaco. On 6 July a satellite image showed a steam-and gas plume drifting W. On 7 and 9 July steam plumes rose 100 m above the crater.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 June-3 July 2012

IG reported that during 27 June-2 July visual observations of Tungurahua were limited due to cloud cover. An explosion on 27 June produced "cannon shot" sounds, along with an ash plume that rose 3 km above the crater and drifted W. Ashfall was reported in Manzano (8 km SW).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 June-26 June 2012

IG reported that during 20-26 June visual observations of Tungurahua were limited due to cloud cover. Incandescence from the crater was observed at night on 20 June. An explosion on 21 June produced an ash plume that rose less than 1 km above the crater and drifted W. Small lahars descended the Achupashal and La Pirámide drainages on the NW flank on 24 June.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 June-19 June 2012

IG reported that during 13-19 June visual observations of Tungurahua were limited due to cloud cover. On 13 June ash plumes rose 2-2.5 km above the crater and drifted NE and N. Ashfall was reported in Cusúa (8 km NW) and Bilbao (8 km W). An explosion the next day caused windows to vibrate in areas 8 km SW and N. Steam plumes rose 0.5-2 km above the crater during 16-18 June. Windows in Manzano (8 km SW) vibrated during 18-19 June, and ashfall was reported in Palitagua, Runtún (6 km NNE), and Choglontús (SW).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 June-12 June 2012

IG reported that during 6-12 June visual observations of Tungurahua were limited due to cloud cover. On 7 June lahars traveled SW down the Mapayacu drainage, carrying blocks 10-20 cm in diameter. Lahars also descended the Achupashal (NW) and El Confesionario (WSW) drainages, causing a temporary closure of the Baños-Penipe highway. On 10 June an explosion was detected by the seismic network; windows vibrated and ash fell in Manzano (8 km SW). An explosions was heard the next day, as well as sounds resembling rolling blocks. An ash plume rose 3 km above the crater and drifted W and E. Ashfall was reported in Manzano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 May-5 June 2012

IG reported that during 30 May-5 June visual observations of Tungurahua were sometimes limited due to cloud cover. On 30 May gas-and-ash plumes rose from the crater and ash fell on the upper flanks. The next day gas-and-ash plumes rose 200 m above the crater and drifted W. On 3 June gas-and-ash plumes rose 100 m above the crater and an ash plume drifted NW. Lahars descended multiple drainages on the W flank. On 5 June ashfall was reported in Pondoa (8 km N), Juive (7 km NNW), Runtún (6 km NNE), Chacauco (NW), and Chontapamba (W), and steam emissions rose 1 km above the crater and drifted E.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 May-29 May 2012

IG reported that during 23-24 May gas-and-ash plumes from Tungurahua drifted SW, W, and NW. Ashfall was reported in Mapayacu (SW), Puela (8 km SW), Manzano (8 km SW), Cahuají (8 km SW), and Riobamba (30 km S). An explosion detected on 25 May was accompanied by roaring and sounds resembling rolling blocks. An ash plume rose 2.5 km above the crater and drifted NW. A steam-and-gas plume rose 200 m and drifted W. Cloud cover prevented observations during 26-29 May. Ashfall was reported in Manzano and Choglontus (SW) on 29 May.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 May-22 May 2012

IG reported that during 16-22 May visual observations of Tungurahua were often limited due to cloud cover. On 16 May a steam-and-gas plume drifted W and lahars descended the W flank. On 18 May ashfall was reported in Manzano (8 km SW), Choglontus (SW), Chontapamba (W), Yuibug, Puela (8 km SW), and high in the Mapayacu drainage (SW). Roaring was heard on 22 May, and slight ashfall was reported in Manzano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 May-15 May 2012

IG reported that during 9-15 May visual observations of Tungurahua were often limited due to cloud cover. On 10 May a steam plume with low ash content rose 200 m above the crater and drifted W. Seismicity increased on 12 May. Explosions caused windows to vibrate in areas near the volcano. Sounds resembling blocks rolling down the flanks as well as roaring noises were reported. A plume with low ash content rose 2-3 km above the crater and drifted W and NW. The next day a plume rose 200 m above the crater and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 May-8 May 2012

IG reported that during 2-8 May visual observations of Tungurahua were often limited due to cloud cover. Explosions were heard in Baños on 2 May and ashfall was reported in Pillate (7 km W) the next day. On 4 May steam emissions rose from the crater and an ash plume drifted W. Ashfall was reported in Pillate and Choglontus (SW). On 6 May explosions were detected and roaring was heard. An ash plume rose 1.5 km above the crater and drifted WSW. Ashfall covered houses and pastures in Bilbao (8 km W) and Pillate. Ash also fell in Chacauco. An ash plume drifted W on 7 May; ashfall was reported in Bilbao, Pillate, Mapayacu (SW), Cevallos (23 km NW), Pillate (7 km W), and Chacauco.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 April-1 May 2012

IG reported that during 25-30 April visual observations of Tungurahua were occasionally limited due to cloud cover. On 27 April a steam-and-ash plume rose 200 m above the crater and drifted WNW. On 30 April tremor was detected then followed by an ash plume that rose 4 km above the crater and drifted WNW. Ash fell in Manzano (8 km SW), Choglontus (SW), and Cahuají (8 km SW). At night observers in the SW noted incandescent blocks that that traveled 1.5 km down the flank. On 1 May steam-and-ash plumes drifted W producing ashfall in Bilbao (8 km W), Motilones (W), Cotaló (8 km NW), Pillate (7 km W), Chacuaco, Choglontus, Cahuají, and Manzano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 April-24 April 2012

IG reported that on 18 April a plume with low ash content rose 2 km above Tungurahua and drifted NW. Ashfall was reported in Juive (7 km NNW) and Cusúa (7 km NW). The next day, steam rose 1 km above the crater and drifted W, and lahars descended the W and SW flanks. On 20 April steam plumes rose 500-800 m and drifted W. A moderate-sized explosion on 22 April produced "cannon shots" and sounds resembling blocks rolling down the flanks. Rice-sized tephra fell in Pillate (7 km W). Lahars descended the Choglontus (SW), Confesionario (WSW), Romero Ingapirca, and Chontapamba (W) drainages, causing the Baños-Penipe road to close near Chontapamba. On 24 April a steam-and-ash plume rose 2 km above the crater.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 April-17 April 2012

IG reported that during 11-15 April visual observations of Tungurahua were occasionally limited due to cloud cover. On 11 April an ash plume rose 5 km above the crater and drifted NE and SE. Ashfall was reported in areas 8 km SW. An explosion on 12 April was followed by ashfall in multiple areas including Ambato (31 km NW), Cusúa (8 km NW), and Bilbao (8 km W). A small ash plume drifted ESE on 13 April and steam plumes drifted SE during 13-14 April. Fumarolic activity in the crater was observed on 15 April.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 April-10 April 2012

IG reported that during 4-8 April visual observations of Tungurahua were limited due to cloud cover. During 9-10 April ash-and-steam plumes rose 2-3 km above the crater and drifted from NE to SE. Explosions were heard in areas near the volcano. Ashfall was reported in Capil, Palictahua, and Los Toctes on 9 April. Lahars descended the W flank on 10 April and caused the road between Baños and Penipe to close.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 March-3 April 2012

IG reported that during 28 March-3 April visual observations of Tungurahua were mostly limited due to cloud cover. A plume rose 800 m above the crater on 1 April and ashfall was reported in Pillate (7 km W), Choglontus (13 km WSW), and Motilones (W). Lahars descended the Pingullo and Achupashal (NW) drainages, carrying material 30 cm in diameter and causing a temporary road closure.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 March-27 March 2012

IG reported that, although visual observations of Tungurahua during 21-25 March were occasionally limited due to cloud cover, steam plumes rose 0.5-4 km above the crater and drifted SW, W, NW, and NNE. On 21 March incandescence from the crater was observed and roaring noises were noted. The next day a steam-and-ash plume rose to a low height, and during 22-23 March ashfall was reported in Runtún (6 km NNE). Heavy rain during 24-25 March generated lahars in the Pampas area to the S and caused flooding in the sectors of Puela (8 km SW), Palitahua (S) and Ulba (NNE). Activity increased on 26 March. Roaring was heard in multiple areas. An ash plume rose 3 km above the crater and drifted NNE; ashfall was reported in Ventanas, Cusúa (8 km NW), Pondoa (about 8 km N), Baños (9 km N), San Francisco, and Río Verde.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


14 March-20 March 2012

IG reported that, although visual observations of Tungurahua during 14-20 March were mostly limited due to cloud cover, steam plumes were noted on 18 March which drifted W. On 19 March explosions were detected by the seismic network. During brief periods where the crater was visible, observers noted incandescence emanating from the crater and a few blocks rolling 200 m down the flank. Slight ashfall was reported in Choglontus (8 km SW), Manzano (8 km SW), and Penipe (15 km SW) the next morning.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 March-13 March 2012

IG reported that, although visual observations of Tungurahua during 6-11 March were sometimes limited due to cloud cover, steam plumes were noted on 6 and 8 March, and a gas-and-ash plume that rose 500 m above the crater was observed on 7 March. Slight ashfall was reported in Choglontus (13 km WSW) on 7 March. An ash plume rose 1 km above the crater on 11 March and drifted SE. Lahars descended the Chacauco (NW) and Mapayacu (SW) drainages. The next day seismicity increased and an ash plume rose 2-3 km above the crater that drifted W and SW. During 12-13 March ashfall was reported in Choglontus and Manzano (8 km SW).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 February-6 March 2012

IG reported that during 29 February-2 March cloud cover prevented views of Tungurahua. On 3 March seismicity increased. Clouds mostly prevented observations; during breaks in the cloud cover ash plumes were observed rising 3 km above the crater and drifting S and SW. Explosions ejected blocks that rolled down the flanks. Two of the explosions generated sounds resembling cannon shots, and vibrated windows. Ashfall was reported in Choglontus (13 km WSW), Manzano (8 km SW), Cahuají (8 km SW), and Motilones (W). On 4 March ashfall was reported in Yuibug and observers noted hot deposits from a small pyroclastic flow that occurred high in the Achupashal drainage (NW). Ash plumes observed during breaks in the cloud cover on 5 March rose 1 km and drifted W. Ash again fell in Choglontus. Clouds prevented observations on 6 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 February-28 February 2012

IG reported moderate activity at Tungurahua during 22-28 February. Steam plumes with some ash content rose to altitudes of 1-2 km (3,300-6,500 ft) a.s.l. and drifted W during 22-24 February. Ash fall was reported in Palitahua (6 km SSW), Choglontus (13 km WSW), and Manzano (8 km SW) on 23 February, and in the Mapayacu (SW) and Achupashal (NW) gorges on 24 February. Strombolian activity was observed on 24 February, and incandescence material that rose as high as 500 m above the crater fell on the W and NW flanks. Ashfall was reported to the SW in Manzano again on 25 February. A steam-and-ash plume rose as high as 800 m above the crater and drifted W on 26 February. Crater incandescence was observed on 23 and 27 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 February-21 February 2012

IG reported continuing activity at Tungurahua during 15-21 February. Increased seismicity and constant harmonic tremor were detected on 16 February. Based on information from the Guayaquil MWO and IG, the Washington VAAC reported that during 17-18 February emissions rose to an altitude of 6 km (19, 500 ft) a.s.l. IG also noted that a steam plume with small amounts of ash drifted WSW on 19 February and W on 21 February.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


1 February-7 February 2012

IG reported a new episode of activity from Tungurahua on 4 February with an explosion that produced roaring heard 14 km NW in Palitahua and Guadalupe. On 4 February an ash plume rose to altitudes of 7-8 km above the crater and drifted NE; lapilli fall was reported in Baños (9 km N), Pillate (7 km W), and Juive (7 km NNW). IG staff aboard a commercial flight on 4 February observed an ash plume that rose to an altitude of 1 km above the crater and drifted W. Ashfall and roaring noises were reported in Baños, Pillate, Juive, Pondoa (8 km N), Pelileo ( about 7 km NW), Guadalupe, Cevallos (23 km NW), and Patate (NW). A pyroclastic flow descended into the Achupashal drainage (NW). At night incandescent blocks ejected by an explosion traveled 1 km down the flanks. On 5 February clouds prevented views of the volcano, though loud "cannon shots" were heard in Baños and Juive, and ashfall was reported in Manzano (8 km SW). Clouds prevented views of the volcano during 6-7 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 January-24 January 2012

IG reported that during 17-22 January low-level seismic activity was detected at Tungurahua and cloud cover mostly prevented observations. On 17 and 20 January steam plumes rose 500 m above the crater. Muddy water in the Achupashal and Pirámide drainages on the NW flanks was noted on 20 January, and a lahar traveled down the Pampas drainage on 21 January. Seismic activity slightly increased during 23-24 January.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 January-17 January 2012

IG reported a new episode of activity and increased seismicity from Tungurahua during 11-17 January. On 12 January ashfall was reported in Manzano (8 km SW), Cahuají (8 km SW), and Choglontus (13 km WSW). A lahar descended the Achupashal drainage, carrying blocks up to 1 m in diameter, and caused the road to Baños (9 km N) to be closed. Cloud cover prevented observations of the crater. On 13 January ash-and-gas emissions were observed, and ash plumes rose as high as 7 km (23,000 ft) a.s.l. and drifted W. Ash-fall was reported in Palitahua (6 km SSW) and roaring noises were heard in Cusúa (8 km NW) and Manzano. On 14 January ash emissions rose 500 m above the crater and drifted WSW; ashfall was reported in Choglontus, Palitahua, and Manzano. Clouds obscured views on 15 January; however ashfall was reported in Palitahua and Manzano. Lahars descended drainages in Juive (NW) and Pondoa (N), carrying blocks 10-20 cm in diameter.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 January-10 January 2012

IG reported a decrease in activity from Tungurahua during 4-10 January. On 4 January steam plumes rose as high as 500 m above the crater and drifted W. Additional steam plumes observed on 8 January also drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 December-3 January 2012

IG reported moderate seismic activity at Tungurahua during 28 December-3 January. On 31 December small steam emissions were observed, and on 3 January a gas-and-steam plume rose 200 m above the crater. Ash-fall from last week's explosions accumulated to a depth of 2-4 mm in villages to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 December-27 December 2011

IG reported that increased seismicity from Tungurahua was detected during 21-27 December. On 22 December ash plumes rose 500 m above the crater and drifted 2 km W. Ashfall was reported in Baños, Vazcún, and Manzano. One explosion at 0850 generated two small pyroclastic flows that descended the Achupashal and Hacienda drainages. Gas-and-ash plumes rose 4 km a.s.l. and drifted NE. On 23 December ash and gas emissions continued and at night Strombolian activity was observed with blocks rising 500 m above the crater. Ashfall was reported in Cahuají, Manzano, and Choglontus. On 24 December roaring noises were heard and ashfall in Cahuají, Manzano, and Choglontus was reported. An ash plume rose 500 m above the crater and drifted W and SW with ashfall reported in Manzano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


14 December-20 December 2011

IG reported a decrease in activity from Tungurahua during 14-20 December. On 15 December steam plumes rose as high as 300 m above the crater and drifted W. Additional steam plumes observed on 17 December also drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 December-13 December 2011

IG reported that during 7-8 December activity continued at Tungurahua and roaring noises and sounds resembling "cannon shots" were heard. Ash plumes rose to altitudes of 1.5-4.0 km (4,920-16,400 ft) drifting W and NE on 7 December, and W and SW on 8 December. Ashfall was reported in communities to the W, NE, and SW. On 8 December ashfall was reported in Choglontús (SW), Chacauco, Manzano (8 km SW), Bilbao (8 km W), and Pillate (8 km W). Crater incandescence was observed on 10 December, but activity decreased during 10-11 December.

Based on pilot and satellite observations, the Washington VAAC reported that during 7-8 December ash plumes from Tungurahua rose to altitudes of 7.0-7.9 km (23,000 -26,000 ft) a.s.l. and drifted 18.5-24.0 km S and SW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


30 November-6 December 2011

IG reported that seismicity has remained the same from the previous week from Tungurahua, but the number of explosions has increased during 30 November-6 December. Incandescent blocks traveled 1 km down the flanks, and roaring noises and sounds resembling "cannon shots" were reported all week. Ashfall was reported from almost all populations near the volcano during the week. Ash plumes rose to altitudes of 1.5-5.0 km (4,920-16,400 ft) and drifted in multiple directions. On the night of 2 December lahars descended into the drainages and ejected incandescent blocks 500 m above the crater.

Seismicity increased on 3 December. During 3-5 December pyroclastic flows descended on the W flanks. Pyroclastic flows were also reported on the NW flank on 4 December, and large explosions occurred at 0130, 0600, and 1330. Significant ashfall was reported in San Juan, Manzano (8 km SW), and Bilbao (8 km W). On 5 December incandescent blocks were ejected 300 m above the crater and gray ash was deposited mainly to the E. On 6 December incandescence and Strombolian activity was observed.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 November-29 November 2011

IG reported that increased seismicity from Tungurahua was detected at 1540 on 27 November, and at 1650 the seismic network recorded four volcano-tectonic earthquakes. Two small explosions at 1701 and 1705 were followed by a large explosion at 1718. Pyroclastic flows descended the Achupashal, Chotanpamba, and Mandur drainages on the NW and W flanks. Two more large explosions were detected at 1731 and 1735. Incandescent blocks traveled 1 km down the flanks, and roaring noises and sounds resembling "cannon shots" were reported. Ashfall was reported in Manzano (8 km SW), Bilbao (8 km W), and Pillate (8 km W), ash and tephra fell in Cotaló (8 km NW), and tephra fell in Cusúa (8 km NW). At 1905 a pyroclastic flow descended the S and SW flanks.

At 0200 on 28 November an explosion ejected incandescent material that fell on all flanks, and generated a pyroclastic flow that descended the Achupashal drainage. Starting before 0500 until 0900 an almost constant roar was heard and incandescent blocks traveled 1 km down the flanks, especially towards the W and NW. Three pyroclastic flows were noted on the S flank. Windows vibrated at the Tungurahua Observatory (OVT) in Guadalupe (14 km N). During the day, an ash plume rose 3 km above the crater and drifted in multiple directions. White ashfall was reported in Manzano, Choglontús (SW), Pondoa (8 km N), and Runtún (6 km NNE). In the evening incandescent blocks that were ejected 300 m above the crater rolled 400-500 m down the flanks. On 29 November an explosion detected at 0611 produced a small pyroclastic flow that traveled 500 m. Another pyroclastic flow at 0955 traveled 1 km W. Gas-and-ash plumes rose 4 km above the crater and drifted SE and W. According to a news article, people in high risk areas on the flanks, in communities such as Cusúa, Juive, Palictahua, and Manzano, evacuated voluntarily.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Agence France-Presse (AFP)


9 November-15 November 2011

The Washington VAAC reported that on 9 November an ash plume from Tungurahua was identified by a pilot. A later report stated that IG noted no ash emissions from Tungurahua since June, and that only gas-and-steam emissions had been observed that day.

Source: Washington Volcanic Ash Advisory Center (VAAC)


19 October-25 October 2011

Based on a pilot observation, the Washington VAAC reported that on 24 October an ash plume from Tungurahua rose to an altitude of 7.3 km (24,000 ft) a.s.l. and drifted W. Ash was not observed in satellite imagery. [A 9 November VAAC report stated that IG noted no ash emissions from Tungurahua since June.]

Source: Washington Volcanic Ash Advisory Center (VAAC)


5 October-11 October 2011

Based on information from IG, the Washington VAAC reported that on 7 October an ash plume from Tungurahua rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted W. Ash was not observed in satellite imagery. [A 9 November VAAC report stated that IG noted no ash emissions from Tungurahua since June.]

Source: Washington Volcanic Ash Advisory Center (VAAC)


25 May-31 May 2011

The IG reported that during 24-26 May explosions from Tungurahua were detected by the seismic network. On 24 May an ash plume rose to an altitude of 7 km (23,000 ft) a.s.l. Ashfall was reported in areas SW and W. The next day an ash plume drifted W. On 26 May ash plumes were not observed due to cloud cover but ashfall was reported to the SW; cloud cover prevented observations during 27-29 May. Muddy water was observed in multiple drainages during 26-30 May. Lahars on 27 May caused the highway to Baños to close. The highway remained closed during the next two days due to lahar risk.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 May-24 May 2011

IG reported that on 17 May new fumaroles on Tungurahua's W flank, about 1 km below the crater, were observed from the Tungurahua Observatory (OVT) in Guadalupe (11 km N). Explosions during 17-23 May produced gas-and-steam plumes that rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l and mostly drifted SW, W, and NW. Ashfall was reported on most days in areas within 8 km SW, W, NW, N, and NNE, but reached as far as Guadalupe (11 km N), Ambato (31 km NW), and Penipe (15 km SW). On 17 May incandescence emanated from the crater. Blocks were also ejected from the crater, and rolled down the flanks, on 17, 19, and 21 May. Sounds resembling "cannon shots" were occasionally reported. Large windows vibrated on 21 May. Ash-and-gas plumes rose from the crater on 24 May and likely drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 May-17 May 2011

IG reported that, although visual observations of Tungurahua during 11-15 May were often limited due to cloud cover, gas-and-steam plumes were noted during 12-14 May that rose 200-300 m above the crater and drifted E, SE, W, and NW. A small explosion on 15 May produced an ash plume that rose 500 m above the crater and drifted E. An ash plume the next day rose 200 m and drifted E. On 16 May an ash plume rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted E, NE, and N. Incandescent blocks were ejected from the crater and rolled up to 500 m down the flanks. Ashfall was reported in the region of the Negro river.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 May-10 May 2011

IG reported that, although visual observations of Tungurahua were occasionally limited due to cloud cover, ash plumes were noted during 4-6 May that rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted W. Ashfall was reported in Alao, S of Riobamba (30 km S) on 4 May and in Manzano (8 km SW) on 5 and 7 May. Cloud cover prevented observations during 7-9 May. Roaring was also reported during 4-9 May. An explosion on 10 May produced an ash plume that rose to an altitude of 10 km (32,800 ft) a.s.l. and drifted W and NW. Slight ashfall was reported in areas as far as 23 km NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 April-3 May 2011

IG reported that, although visual observations of Tungurahua were occasionally limited due to cloud cover during 26 April-3 May, ash plumes were noted daily and rose to altitudes of 7-12 km (23,000-39,400 ft) a.s.l. The plumes drifted in multiple directions. Ashfall was reported daily in areas within 8 km NNE, N, NW, W, and SW. On 27 and 29 April and during 1-3 May ashfall was reported in areas farther away including the Tungurahua Observatory (OVT) in Guadalupe (11 km N), Ambato (31 km NW), Mocha (25 km W), and 40 km WSW. Blocks ejected from the crater rolled down the flanks on most days and explosions periodically caused doors and windows to vibrate. On 29 April tremor intensified and Strombolian activity increased. According to news articles, an IG scientist noted that boulders the size of a truck were ejected from the crater, causing impact craters 10 m wide where they fell on the flanks. About 300 people evacuated.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Batangas Today


20 April-26 April 2011

On 22 April, IG reported that in recent months the seismic network at Tungurahua detected volcano-tectonic earthquakes, indicating increased pressure in the volcano. Deformation of the NW quadrant that began in early February was slow but continuous, and then accelerated during the previous nine days. On 21 April gas-and-ash plumes caused fine ashfall in Choglontús and Cahuají (8 km SW), Pillate (8 km W), Cotaló (8 km NW), Juive (7 km NNW), and Baños (8 km N). Strombolian activity was seen at night, producing small lava fountains and incandescent blocks that rolled 1 km down the flanks. Roaring was heard and a few explosions occurred during 21-22 April. IG recommended that residents do not go within 3 km of Tungurahua's crater. On 26 April six explosions were detected and constantly-generated ash plumes rose to an altitude of 12 km (39,400 ft) a.s.l. Plumes drifted W and NW, causing steady ashfall in areas downwind. Structures vibrated in surrounding areas, including in Baños.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 January-18 January 2011

The IG reported that during 5-17 January activity at Tungurahua continued to decrease and ash was absent from plumes. At night during 11-12 January incandescence from the crater was observed. Although cloudy weather often prevented observations during 11-18 January, weak steam plumes were occasionally observed rising from the crater.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


5 January-11 January 2011

On 5 January IG reported that, after moderately-sized explosions during 24-25 December, activity at Tungurahua had decreased. IG noted that during this time seismicity decreased and explosions had not occurred, deflation was detected, sulfur dioxide emissions gradually reduced, and decreases in the amount of ash present in plumes was noted. Although cloudy weather often prevented observations during 5-11 January, steam plumes were occasionally observed and rose above the crater to low heights.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 December-4 January 2011

Although storm clouds occasionally prevented observations of the summit area, IG reported that steam plumes were observed almost daily during 29 December-4 January. Incandescence from the crater was occasionally observed at night. On 30 December a steam-and ash plume rose 500 m above the crater and drifted W. On 2 January a small explosion produced an ash plume that also rose 500 m above the crater and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 December-28 December 2010

The IG reported that during 21-23 December steam-and-ash plumes rose from Tungurahua and drifted NW, W, and SW. Ash fell in Bilbao, 8 km W, on 22 December. On 23 December explosions caused windows to vibrate in Cusúa (8 km NW), Pondoa (8 km N), and Baños (9 km N), producing sounds resembling "cannon shots." One of the explosions ejected incandescent material that rolled down to the lower flanks. Another produced a steam-and-ash plume that rose to an altitude of 11 km (36,100 ft) a.s.l. and drifted W and NW.

On 24 December steam-and-ash plumes rose 8 km (26,200 ft) a.s.l. and drifted NW and SW. Explosions caused windows to vibrate and sounds resembling "cannon shots" were noted. On 25 December incandescent material was ejected from the crater and rolled 2 km down the flanks. Steam-and-ash plumes rose from the crater during 25-27 December; ashfall was reported in Choglontús (SW) on the 25th. Ash plumes observed on 28 December drifted W. Incandescence from the crater was also noted.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 December-21 December 2010

The IG reported that during 14-15 December gas-and-ash plumes from Tungurahua rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted SW, NE, and E. Slight ashfall was reported in Puto, 50 km E. Explosions caused "cannot shot" noises, and blocks rolled down the flanks. Incandescence from the crater was observed at night. The next day steam-and-gas plumes, with occasional pulses of ash, rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted E and W. Roaring was heard and ashfall was reported in Palictagua.

Although storm clouds occasionally prevented observations of the summit area, steam-and-gas plumes were seen during 17-18 and 21 December drifting S, SW, and W, and a plume was observed drifted S on 19 December. On 20 December ashfall was reported in areas to the N and NNW. Lahars descended the Mapayacu (SW) and Bramaderos drainages, carrying blocks up to 90 cm in diameter and depositing them in the Puela river to the S. Later that day, an explosion caused windows to vibrate in multiple areas. Incandescent blocks rolled 2 km down the flanks. A plume rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 December-14 December 2010

During 7-14 December, IG reported that ash-and-steam plumes from Tungurahua rose to altitudes of 6-9 km (19,700-30,000 ft) a.s.l. and drifted WNW, W, SSW, and SW. Ashfall was reported in areas as far as 8 km NW, 15 km W and SW, and 30 km S. Roars and sounds resembling "cannon shots" were noted almost daily. Explosions often caused windows and structures to vibrate. At night during 7-8 December Strombolian explosions ejected material 600 m above the crater. Blocks rolled 600-800 m down the flanks. On 9 December a pyroclastic flow traveled 3 km down the NW flank. During 9-10 and 12 December incandescent blocks rolled down the flanks. During 12-13 December incandescent blocks were ejected 500 m above the crater.

On 14 December, IG issued a special report stating that a lava flow with an estimated volume of hundreds of thousands of cubic meters traveled 1 km down the W flank on 4 December. The report noted that the flow was the second since the eruptions onset in 1999.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 December-7 December 2010

During 2-3 December, IG reported that Strombolian activity from Tungurahua was seen at night. Ash plumes on 3 December rose to an altitude of 8 km (26,200 ft) a.s.l. and ashfall was reported in nearby areas. On 4 December, a sudden increase in tremor detected by the seismic network was followed by intense roaring noises, an increase in the number and intensity of explosions, and window and ground vibrations. Pyroclastic flows descended the N and W drainages at 0939 and continued to occur in those and additional drainages until 1522, including Cusúa, Mandur, and Juive (NW), as well as Rea, Choglontús, and Mapayacu (SW). Ashfall occurred in uninhabited regions to the S and SE. According to news articles, people within 8 km of the summit were evacuated.

On 5 December, satellite images showed ash plumes drifting SW. Ashfall was reported in areas within 8 km SW, W, NNW, and NW. Explosions caused windows to vibrate. During 5-6 December, blocks ejected from Strombolian activity rolled 1 km down the flanks. On 6 December, ash plumes rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted NW, W and SW, causing ashfall downwind. Gas-and-ash plumes on 7 December rose to altitudes of 7-8 km (23,000-26,200 ft) a.s.l. and drifted SW and W. Ashfall resulted in deposits up to 1 mm thick in areas to the W. Ejected blocks rolled 1-2 km down the flanks and explosions vibrated windows.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Reuters


24 November-30 November 2010

The IG reported that on 22 November an explosion ejected incandescent blocks that fell onto the flanks 1.5 km below the crater rim, and produced an ash plume that rose to altitudes of 11-12 km (36,100-39,400 ft) a.s.l. Ashfall was reported in multiple areas to the W and SW. Smaller explosions produced ash plumes that rose to altitudes of 7-8 km (23,000-26,200 ft) a.s.l. and drifted NE and E. Lahars descended a SW drainage and temporarily dammed the Puela river. During 23-25 November, explosions produced ash plumes that rose less than 7 km (23,000 ft) a.s.l. Ashfall was reported in areas within 8 km N, NNE, W, and SW. Strombolian activity was seen at night.

During 25-26 and 29 November incandescent blocks were observed rolling down the flanks. During 26-30 November, steam-and-ash plumes rose to altitudes of 5.5-9 km (18,000-29,500 ft) a.s.l. and drifted SW and W. Plumes also drifted NW on 28 November. Ashfall was reported in areas within 8 km downwind, and roaring was occasionally reported. At night during 28-29 November Strombolian activity ejected blocks that rolled 400 m down the flanks. Satellite imagery on 29 November showed an increase in sulfur dioxide concentrations.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 November-23 November 2010

Based on Air Force Weather Agency (AFWA) reports, pilot observations, and analyses of satellite imagery, the Washington VAAC reported that on 22 November an eruption from Tungurahua produced an ash plume that rose to an altitude of 7.6 km (25,000 ft) a.s.l. and drifted 37 km SW. Subsequent satellite images showed a detached ash cloud that became difficult to discern in images about 230 km SW of the volcano. Pilots reported additional ash emissions that rose to an altitude of 6.4 km (21,000 ft) a.s.l. On 23 November satellite images showed an ash plume drifting S. IG reported that an ash plume rose to an altitude of 7 km (23,000 ft) a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


28 July-3 August 2010

The IG reported that during 28 July-2 August steam emissions rose from Tungurahua's crater. On most days steam plumes with minor ash content rose 1-2 km above the crater and drifted NW or W. Minor ashfall was reported to the SW in the Choglontus area during 28-29 July.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 July-27 July 2010

Observations of Tungurahua's summit area during 21-27 July were sometimes not possible due to inclement weather. Ash plumes seen during 21-23 July rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. and drifted W and NW. Ashfall was reported in areas within 10 km NW, W, and SW during 22-24 July. Steam plumes were seen rising 200 m above the crater on 25 July and an explosion was heard on 26 July. On 27 July a series of explosions was detected by the seismic network. Roaring noises were followed by vibrating windows in areas to the N and NW. Slight ashfall was noted in areas to the SW and W, and as far as 23 km NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


14 July-20 July 2010

Observations of Tungurahua's summit area during 13-20 July were sometimes not possible due to inclement weather. On 13 July incandescent blocks were seen rolling down the flanks at night and ashfall was reported in areas 8 km SW. Incandescence from the crater was seen the next night and ashfall was again reported in areas to the SW. During 15-18 July steam-and-ash plumes were observed and occasionally drifted SW. Ashfall was noted in areas within 8 km SW, W, and NW. Lahars descended drainages to the SW, NW, and N on 15 July. Rolling blocks on the flanks were seen after explosions on 18 July. During 19-20 July steam plumes drifted NW and W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 July-13 July 2010

Observations of Tungurahua's summit area during 7-13 July were often not possible due to inclement weather. On 7 July steam-and-ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted WSW. The next day explosions were accompanied by acoustic waves. A steam plume rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted NW. Ashfall was reported in Cusúa about 8 km downwind. Incandescence from the crater was seen during both nights. Ash-and-steam plumes were seen on 9 July. Ashfall was reported in a few areas 8 km SW and W. On 10 and 12 July plumes with low ash content drifted W. Ashfall was reported 7-8 km to the W and NNW on 12 July. Incandescent blocks descended the flanks at night to 500 m below the crater on 9 and 12 July.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 June-6 July 2010

Observations of Tungurahua's summit area during 30 June-6 July were mostly not possible due to inclement weather. On 2 July, gas plumes were seen drifting WSW during breaks in the cloud cover. Ashfall was reported in areas 8-9 km W and SW, and as far away as 40 km WSW in San Juan. Incandescence from the crater was seen at night and slight roaring was heard. Ashfall was again reported in areas 8-9 km W and SW during 3-4 July. Steam-and-ash plumes were seen on 5 July and rose to an altitude of 7 km (23,000 ft) a.s.l. Ash fell in areas 8 km to the SW. Steam-and-ash plumes were again seen on 6 July; ashfall was reported in areas 8 km W, NW, and N.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 June-29 June 2010

Although storm clouds occasionally prevented observations of Tungurahua's summit area, steam-and-gas plumes were seen on 22 and 23 June and steam-and-ash plumes were seen during 24-28 June. The plumes rose as high as 1 km above the crater and drifted NW, W, and SW. During most days ash fell in areas within 8 km SW and occasionally in areas 8 km W and NW. Roaring noises were sometimes heard, and on 25 June were followed by vibrating windows 8 km W and SW. Lahars on 26 June traveled down drainages to the NW and W carrying blocks up to 2 m in diameter. On 27 June ashfall was reported from areas 23 km NW and 25 km W. During 27-28 June incandescence emanated from the crater at night.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 June-22 June 2010

Although storm clouds occasionally prevented observations of Tungurahua's summit area during 16-18 June, steam-and-ash plumes were seen that rose to altitudes of 5.5-7 km (18,000-23,000 ft) a.s.l. Daily reports of ashfall came from multiple areas about 8 km W and SW, but ash was noted as far away as 15 km SW on 17 June. Ashfall in Cahuají (8 km SW) covered pastureland, preventing animals from grazing. Roaring noises were occasionally reported. During 17-18 June, incandescence from the crater was seen at night. An explosion was followed by roaring noises, sounds resembling blocks rolling down the flanks, and incandescence.

On 19 June steam-and-ash plumes rose 500 m above the crater and large windows vibrated after noises were heard. The next day snow covered parts of the E and S flanks. Steam-and-gas plumes rose 500 m and drifted SSW, E, and NW during 20-21 June. Lahars in drainages to the SW carried blocks up to 50 cm in diameter. On 21 June ashfall was reported in areas 8 km W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 June-15 June 2010

Although storm clouds occasionally prevented observations of Tungurahua's summit area during 9-12 June, steam-and-ash plumes were seen and rose to altitudes of 5.5-8 km (18,000-29,500 ft) a.s.l. Daily reports of ashfall came from multiple areas within about 8 km NW, W, and SW, but ash was noted as far away as 22 km NW and 25 km W on 9 June. Blocks, including some that were incandescent, occasionally ejected by explosions rolled at most 1 km down the flanks. Explosions caused noises resembling "cannon shots" and vibrating windows almost daily. During 13-14 June steam plumes from the crater and the NW flank rose 500-1,000 m above the crater and drifted W. An explosion on 15 June generated an ash plume that rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 June-8 June 2010

Although storm clouds often prevented observations of Tungurahua's summit area during 1-8 June, steam-and-ash plumes generated by explosions were sometimes seen and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. Larger explosions occasionally produced ash plumes that rose as high as an altitude of 9 km (29,500 ft) a.s.l. Daily reports of ashfall came from multiple areas within about 8 km NW, W, and SW. Explosions ejected blocks (that were occasionally incandescent) almost daily as high as 1 km above the crater rim. The blocks that fell outside of the crater descended the flanks a maximum distance of 2 km. Noises resembling "cannon shots" associated with explosions were often followed by vibrating windows and doors in local areas; on 6 June large windows vibrated at Tungurahua Observatory (OVT) in Guadalupe, 11 km N.

On 2 June a pyroclastic flow traveled 1.5 km down the NW flank. During 5-7 June ashfall was noted in areas farther away, including at OVT and Cevallos, 23 km NW. Explosions on 7 and 8 June generated ash plumes that rose to altitudes of 9-10 km (29,500-32,800 ft) a.s.l. and drifted W. On 7 June another small pyroclastic flow traveled 1.5 km down the NW flank.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 May-1 June 2010

The IG reported that on 26 May a strong explosion from Tungurahua generated pyroclastic flows and an ash plume that rose to an altitude of 12 km (39,400 ft) a.s.l. and drifted W and SW. Ashfall was reported in areas to the S and SW, including Riobamba (30 km S). Noises resembling "cannon shots" associated with the explosion were heard as far away as Guadalupe, 11 km N. The pyroclastic flows were small and traveled 800-1,000 m down the N, NW, W, and SW flanks; they did not reach populated areas. Poor visibility mostly prevented observations of the crater the next day, but no activity was seen when the crater was visible. Slight ashfall was reported in Cahuají.

On 28 May another strong explosion produced an ash plume that rose to an altitude of 15 km (49,200 ft) a.s.l. and drifted WSW. Pumice blocks fell in local neighborhoods (likely 6-8 km away), and ash fell in several areas between Tungurahua and Guayaquil (about 180 km SW), and beyond. Pyroclastic flows traveled as far as 3 km down the NW, W, and SW flanks, but again did not reach populated areas. According to news articles, residents from two towns about 8 km NW were evacuated and the airport in Guayaquil was temporarily closed because the runways were covered in ash. Other flights passing through the area were rerouted.

During 28-29 May seismicity increased and 5-10 explosions were detected per hour. Explosions ejected incandescent blocks that fell 1-2 km below the summit. Ashfall was heavy in Runtún, 6 km NNE, at night on 28 May, and lighter in Juive and Puntzán, 7 km NW, the next morning. During 29-30 May explosions occurred at a rate of about 10 per hour. Several roaring noises were noted and "cannon shot" noises caused large windows nearby to vibrate. Incandescence around the crater was seen occasionally at night, during periods of clearer viewing. On 31 May and 1 June explosions generated audible "cannon shots" and ejected incandescent blocks as high as 1.5 km above the crater rim; several of the blocks rolled nearly 1 km down the flanks. Steam-and-ash plumes rose to altitudes of 7-9 km (23,000-29,500 ft) a.s.l. and drifted W, SW, N, and NE, causing ashfall in areas downwind.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Reuters


5 May-11 May 2010

The IG reported that during 4-5 and 7-8 May lahars traveled down Tungurahua's N, W, and SW flanks. No activity from the crater was noted during 5-11 May, although meteorological cloud cover often prevented observations.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 March-23 March 2010

The IG reported that although inclement weather often prevented observations of Tungurahua during 17-23 March, steam-and-gas plumes were occasionally seen. Explosions were detected by the seismic network and heard in nearby areas on 19 March; the largest explosion generated an ash plume that rose to an altitude of 9 km (29,500 ft) a.s.l. Ashfall was reported in Choglontús, to the SW. On 20 March small lahars affected the Baños-Penipe highway. On 22 March, ashfall was again reported in areas to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 March-16 March 2010

The IG reported that rains during 9-11 March caused lahars to descend drainages on Tungurahua's NW, W, SW, and S flanks. Lahars caused the road to Baños to close on 10 March and carried blocks up to 50 cm in diameter on 11 March. Fumarolic activity in the crater was seen during 12-15 March when the weather was clearer.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 March-9 March 2010

The IG reported that on 2 March an ash plume from Tungurahua rose to an altitude of 8.5 km (28,000 ft) a.s.l. and drifted NW. Although inclement weather often prevented observations of the volcano during 3-9 March, fumarolic activity in the crater was seen on 6 and 8 March. Ash fell in areas to the SW on 3 and 4 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 February-2 March 2010

During 24-28 February, IG reported that as many as 11 explosions from Tungurahua were detected by the seismic network; explosions were not detected on 1 or 2 March. Although inclement weather occasionally prevented observations of the volcano, ash plumes were seen during 24 February-1 March rising to altitudes of 6.5-8 km (21,300-26,200 ft) a.s.l. and drifting SW and W. Ashfall was noted almost daily in areas downwind.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 February-23 February 2010

The IG reported that explosions from Tungurahua were detected by the seismic network during 16-23 February. Although inclement weather often prevented observations of the volcano, ash plumes were seen rising to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. and drifting S, SW, W, and ENE. Ashfall was noted almost daily, in areas to the SW and S. Blocks rolled down the flanks on 18 February. Lahars descended NW and W drainages on 20 February and a SW drainage on 22 February. On 21 February small block avalanches on the N flank generated pyroclastic flows.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 February-16 February 2010

The IG reported that during 10-16 February explosions from Tungurahua were detected by the seismic network. The explosions often produced sounds resembling "cannon shots" and caused windows and structures to occasionally vibrate. Blocks ejected from the crater fell onto the flanks and rolled as far as 2 km from the crater. Ash plumes rose to altitudes of 5.5-9 km (18,000-29,500 ft) a.s.l. On 11 February, a small pyroclastic flow seen from Tungurahua Observatory (OVT) in Guadalupe, 11 km N, descended the N and NNW flanks. Ashfall was seen daily and impacted areas to the NW, W, SW, and S. Ashfall was 3 mm thick in Choglontus, Cahuají, and Pillate on 12 February, and 1 mm thick in Choglontus on 14 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 February-9 February 2010

The IG reported that 14-51 explosions from Tungurahua were detected by the seismic network during 3-9 February. Inclement weather often prevented observations of the volcano; an ash plume was seen rising to an altitude of 7 km (23,000 ft) a.s.l. Ashfall was noted almost daily in areas to the SW, W, and NW, and was particularly heavy towards the end of the reporting period. Roaring noises and sounds resembling "cannon shots" were heard. Explosions sometimes caused windows and structures to vibrate, including large windows at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N. Occasionally at night incandescence emanated from the crater and incandescent blocks rolled down the flanks as far as 1 km. On 3 February lahars descended drainages to the W and SW, carrying tree trunks and blocks up to 1 m in diameter, and causing the road from Riobamba to Baños to close. Strombolian activity from the crater was seen during 6-8 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 January-2 February 2010

The IG reported that during 26 January-2 February explosions from Tungurahua were detected by the seismic network. Inclement weather occasionally prevented observations of the volcano; ash plumes were seen rising to altitudes no higher than 8 km (26,200 ft) a.s.l. Ashfall was noted almost daily in areas to the SW, W, and NW. Roaring noises and sounds resembling "cannon shots" were reported. During 26 and 28-30 January lava fountains were seen and sometimes ejected incandescent blocks that fell onto and rolled down the flanks. On 31 January, a lahar descended the Chontapamba drainage to the W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 January-26 January 2010

The IG reported that during 20-26 January explosions from Tungurahua were detected by the seismic network. Inclement weather often prevented observations of the volcano; occasionally ash plumes were seen rising to altitudes of 5.3-8 km (17,400-26,200 ft) a.s.l. Ashfall was noted almost daily in areas to the SW and sometimes to the W and NW. Roaring noises, sounds resembling "cannon shots," and vibrating windows were reported. During 20-23 January lava fountains and explosions ejected incandescent blocks that fell onto and rolled down the flanks. Blocks were also seen rolling down the flanks on 24 and 25 January. On 26 January, an explosion generated an ash plume that rose to an altitude of 9 km (30,000 ft) a.s.l. Ashfall was reported in areas to the NW, W, and WSW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 January-19 January 2010

The IG reported that during 13-14 January explosions from Tungurahua ejected incandescent material 1 km above and 1.5 km away from the crater, onto the flanks. Explosions produced noises resembling "cannon shots" and caused windows and structures to vibrate. Gas-and-ash plumes rose to altitudes of 7-8 km (23,000-26,000 ft) a.s.l. and drifted W and SW, causing ashfall. On 15 January, although meteorological clouds mostly prevented observations, an ash plume was seen rising to an altitude of 6 km (19,700 ft) a.s.l. Cloud cover prevented observations during the next two days. On 17 January, ashfall was reported in areas W and SW. Lahars descended drainages to the W and NW, causing the road to Baños to close. On 18 January, Strombolian activity ejected incandescent blocks and an ash plume rose to an altitude of 6 km (19,700 ft) a.s.l. Explosions caused windows and structures to vibrate. Ashfall was reported in areas W and SW on 18 and 19 January.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 January-12 January 2010

The IG reported that during 5-6 January a gas-and-ash plume from Tungurahua rose to an altitude of 6.5 km (21,300 ft) a.s.l. and drifted NW. The sulfur dioxide emission rate was 3,200 tons per day, ten times the value measured during the previous months. On 7 January seismic tremor duration and amplitude increased, and signals indicative of explosions were detected. On 6 and 7 January, incandescent blocks were ejected and fell back into the crater. During 8-10 January, cloud cover often prevented observations; on 10 January a steam-and-ash plume rose to an altitude of 6.5 km (21,300 ft) a.s.l. and drifted W. Incandescence from the crater was sometimes seen at night. Ashfall up to 5 mm thick was reported in areas W and SW on 9 and 10 January. Roaring noises and vibrating glass were occasionally noted during the reporting period.

During 11-12 January, activity increased; ash plumes rose to higher altitudes and more explosions were detected. Incandescent blocks were ejected almost 1 km above the crater and 1.5 km away from the crater, onto the flanks. Gas-and-ash plumes rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted in multiple directions. Ashfall was reported in areas to the NNW, W, SW, and S.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 December-5 January 2010

The IG reported steam emissions from Tungurahua during 30 December-3 January. On 1 January, an ash plume rose to an altitude of 5.9 km (19,500 ft) a.s.l. and drifted NW. Slight ashfall was reported the next day in Manzano, 8 km SW. Roaring noises and incandescence from the crater were also reported. On 3 and 4 January, incandescent blocks were ejected from the crater. Based on information from the Guayaquil MWO and SIGMET notices, the Washington VAAC reported that ash plumes rose to altitudes of 6.7-9.1 km (22,000-30,000 ft) a.s.l. and drifted W. Thermal anomalies were detected in satellite imagery. On 4 January, ashfall was reported in areas to the W and SW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 August-25 August 2009

The IG reported that inclement weather often prevented observations of Tungurahua during 19-25 August, although steam-and-gas emissions were observed rising from the crater during 23-24 August. On 19 August, lahars that descended W drainages carried blocks up to 30 cm in diameter. Lahars also descended W and N drainages on 21 August.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 July-7 July 2009

The IG reported that inclement weather often prevented observations of Tungurahua during 1-7 July; steam-and-ash plumes rose 1 km above the summit and drifted WSW on 1 July. Ashfall was reported in areas to the SW on 2 July. During 2 and 5-7 July, lahars that descended SW and W drainages carrying blocks up to 40 cm in diameter.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 June-30 June 2009

The IG reported that tremor and explosions from Tungurahua were detected by the seismic network almost daily during 23-30 June. A plume with low ash content rose to an altitude of 7 km (23,000 ft) a.s.l. on 23 June and drifted W, and a small ash plume rose 200 m above the crater on 29 June. Cloud cover frequently prevented observations during the rest of the reporting period. Ashfall was occasionally reported in areas to the W and SW. Sounds resembling blocks rolling down the flanks and "cannon shot" noises were sometimes reported. On 23 June, lava fountains at the summit were observed and blocks ejected from the crater rolled as far as 1 km down the flanks. On 27 June, the seismic network possibly detected lahars in area drainages.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 June-23 June 2009

Continued moderate seismic and eruptive activity was reported by the IG during 17-23 June. Explosions with resulting ashfall were reported on most days. Lava fountains were observed on the night of 21 June rising to a height of 500 m above the crater. Incandescent blocks seen over the next two days rolled as far as 2 km downslope.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 June-16 June 2009

The IG reported that during 10-15 June tremor and explosions from Tungurahua were detected by the seismic network. Ash plumes rose to a maximum altitude of 7 km (23,000 ft) a.s.l. during 10-11 and 14 June; cloud cover frequently prevented observations during the reporting period. Ashfall was reported almost daily, mostly to the W. Some explosions were accompanied by "cannon shot" sounds or sounds resembling blocks rolling down the flanks. Windows occasionally vibrated.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 June-9 June 2009

The IG reported that during 3-9 June tremor and explosions from Tungurahua were detected by the seismic network. On 3 June, lahars traveled down multiple drainages. A gas-and-ash plume rose 200 m and drifted SW; cloudy conditions prevented visual observations during the rest of the reporting period. Ashfall was detected in areas to the SW and W on 4 June. On 7 June, noises resembling blocks rolling down the flanks, "cannon shots," and roars were reported. The next day, "cannon shot" noises were followed by the vibration of windows in nearby areas.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 May-2 June 2009

The IG reported that Strombolian activity was seen at night from Tungurahua during 26-28 May, followed by nighttime incandescence at the crater through 1 June. The Washington VAAC reported that during 27-29 and 31 May thermal anomalies were seen on satellite imagery. IG also stated that explosions, "cannon shots," and roaring noises were occasionally reported. On 28 May, steam-and-ash plumes rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted W and SW. Blocks rolled 1 km down the flanks. Ashfall was reported downwind during 28-30 May.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


20 May-26 May 2009

The IG reported that inclement weather often prevented observations of Tungurahua during 20-26 May; ash plumes rose 1-2 km above the summit and drifted W on 22, 24, 25, and 26 May. Occasionally roaring noises were reported and explosions caused structures to vibrate. During 20-23 and 25-26 May, ashfall was reported in areas to the W and SW. During 24-26 May, incandescence from the crater was seen and blocks rolled 100-500 m down the flanks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 May-19 May 2009

The IG reported that inclement weather sometimes prevented observations of Tungurahua during 13-19 May. Roaring noises were occasionally reported. On 13 and 18 May, a fine layer of ash fell in Manzano, 8 km SW. On 15 May, explosions and sounds resembling rolling blocks were noted. An explosion generated a steam-and-ash plume that rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted ENE. During 16-18 May, steam and steam-and-ash plumes drifted NW, W, and E. During 17-18 May, blocks were heard or seen rolling down the flanks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 May-12 May 2009

The IG reported that inclement weather sometimes prevented observations of Tungurahua during 6-12 May. On 6 May, ashfall was reported in Baños, about 8 km N. Steam plumes rose to altitudes below 6.5 km (21,300 ft) a.s.l. during 6-8 May and drifted W. During 9-11 May, roaring noises, "cannon shots," and sounds resembling rolling blocks were reported. On 9 May, an ash plume rose to an altitude of 6 km (19,700 ft) a.s.l. The next day ash plumes rose to an altitude of 8 km (26,200 ft) a.s.l. while roaring noises were very strong.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 April-5 May 2009

During 28 April-5 May, IG reported that, although inclement weather often prevented observations of Tungurahua, steam-and-gas plumes were seen almost daily. The plumes rose to altitudes below 6.8 km (22,300 ft) a.s.l. and drifted SW and W. Lahars descended the Achupashal drainage to the NW on 28 April and the Motilones drainage to the W on 1 May. Incandescence in the crater was seen at night on 30 April. During 29 April and 2-3 May, noises and explosions rattled structures and windows. On 3 May, ashfall was reported in areas to the SW, NW, and N.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 April-28 April 2009

The IG reported that during 22-28 April steam-and-gas plumes occasionally containing ash rose from Tungurahua to an altitude of 6.5 km (21,300 ft) a.s.l. and drifted SW and W. Roaring noises were reported. Ashfall was noted in areas to the SW on 21 April. During 21-22 April, incandescence from the crater was seen; incandescent blocks ejected from the crater on 22 April rolled down the flanks. On 25 April, a lahar descended the Patacocha drainage.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 April-21 April 2009

During 15-21 April, IG reported that clouds mostly prevented observations of Tungurahua; a steam-and-gas plume rose 100 m above the crater on 15 April and an ash plume rose 1 km above the crater and drifted NW on 18 April. Ashfall was reported in areas to the SW and N during 15-16 and 18-19 April. Roaring noises were occasionally heard.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 April-14 April 2009

During 8-14 April, IG reported that clouds mostly prevented observations of Tungurahua; a steam plume seen on 9 April rose 300 m above the crater and drifted SW. On 10 April, slight ashfall was reported in areas to the SW. The next day, a lahar traveled SW down the Mapayacu drainage. On 14 April, a steam-and-gas plume containing some ash rose to an altitude of 7.5 km (24,600 ft) a.s.l. and drifted N.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 April-7 April 2009

During 1-3 and 5 April, IG reported that steam or steam-and-ash plumes from Tungurahua rose a few meters to 1 km above the crater. Plumes drifted S, SW, and NNW. On 6 April, fumarolic plumes rose 500-600 m. Light ashfall was reported about 8 km SW in the town of Manzano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 March-31 March 2009

During 25-27 and 30-31 March, IG reported that steam-and-ash plumes from Tungurahua rose to altitudes of 5.5-7 km (18,000-23,000 ft) a.s.l. and drifted NW, NE, E, and SW. On 25 March, ashfall was reported in areas to the SW and lahars traveled down a drainage to the W. On 26 March, lahars traveled down multiple drainages to the W, SW, and S; a lahar in the Mapayacu drainage to the SW carried blocks up to 2 m in diameter. Inclement weather impaired visual observations during 28-29 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 March-24 March 2009

The IG reported that during 17-18 and 22 March ash plumes from Tungurahua rose to altitudes of 5.5-7.5 km (18,000-24,600 ft) a.s.l. and drifted W, NW, and NNE. Ashfall was reported in areas downwind on 17 and 20 March. On 21 March, lahars carrying blocks up to 30 cm in diameter traveled down the Mapayacu drainage to the SW. Lahars were also seen in the Mandur drainage to the NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 March-17 March 2009

On 11 March, IG reported that a steam-and-ash plume from Tungurahua rose 600 m above the summit and drifted E and NE. Fumaroles on the NE flank were active. On 12 and 16 March, plumes with low ash content rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted NE. Steam plumes were occasionally seen during 13-14 and 17 March, and a plume rose 300-500 m above the summit and drifted E and W on 15 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 March-10 March 2009

The IG reported that inclement weather frequently prevented visual observations of Tungurahua during 4-10 March. Slight ashfall was reported in areas to the NW on 4 March. On 6 March, steam-and-ash plumes rose 500 m above the crater. On 8 March, a steam plumes rose 100 m above the summit and fumaroles on the E flank were active.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 February-3 March 2009

The IG reported that, although cloud cover occasionally prevented visual observation during 24 February-3 March, ash plumes from Tungurahua were seen and rose to altitudes of 5.5-10 km (18,000-32,800 ft) a.s.l. The plumes drifted in multiple directions. Ashfall was reported almost daily in areas to the SW, W, NW, N, and NE. Blocks were sometimes seen or heard rolling down the flanks, and roaring or explosion noises were noted. Strombolian activity at the summit was observed at night on 24 and 25 February. On 25 February, explosions caused the ground and large windows to vibrate. An explosion on 1 March was followed by an ash plume that rose to an altitude of 10 km (32,800 ft) a.s.l. and drifted NW. Incandescence at the crater was noted at night on 2 March.

According to a news article from 3 March, ash covered at least 250 hectares of cropland, and additional land for cattle grazing.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), El Comercio


18 February-24 February 2009

The IG reported that, although cloud cover occasionally prevented visual observation during 18-24 February, ash plumes from Tungurahua were seen and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. The plumes drifted mainly W and NW. Ashfall was reported almost daily and was noted in areas to the SW, W, and NW. Blocks were often seen or heard rolling down the flanks, and roaring or explosion noises were noted. On 18 February, incandescence in the crater was seen and a lahar traveled down a drainage to the W. Strombolian activity at the summit was observed during 19-20 and 22-23 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 February-17 February 2009

The IG reported that although visual observations of Tungurahua were occasionally limited due to cloud cover; gas-and-ash plumes were seen and rose to altitudes of 5.5-7.5 km (18,000-24,600 ft) a.s.l. during 11-17 February. Plumes drifted W, NE, E, and SE. On 11 February, small lahars descended multiple gorges to the NW and S. Incandescence in the crater was seen at night on 11 and 12 February, and roaring was heard on 12 and 16 February. Ashfall was reported in areas to the SW on 12 February and to the N on 14 February. An explosion on 16 February that vibrated windows was followed by ash emissions that generated a plume to an altitude of 8 km (26,200 ft) a.s.l. The plume drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 February-10 February 2009

The IG reported that during 4-8 February visual observations of Tungurahua were limited due to cloud cover; steam-and-ash plumes rose 0.5-1 km above the summit during 7 and 9-10 February. Plumes drifted W and NW. Cannon shots, roaring noises, and sounds resembling blocks rolling down the flanks were seldom reported. Based on pilot observations, the Washington VAAC reported that an ash plume rose to an altitude of 8.5 km (28,000 ft) a.s.l. and drifted SSE. On 4 and 8 February IG reported that ash fell in areas to the SW. Incandescence from the crater was seen at night on 6 February.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


28 January-3 February 2009

The IG reported that although visual observations were limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua drifted NE, W, and SW during 27 January-2 February. Incandescence in the crater was occasionally seen and roaring noises were noted. Ashfall was reported in areas on the SW flank during 30 January, and 1-2 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 January-27 January 2009

The IG reported that during 20, 23, and 25-26 January steam-and-ash plumes from Tungurahua rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted SW and W; cloud cover often prevented visual observations on the other days during 20-27 January. Roaring and explosions were occasionally heard. Incandescence in the crater was noted at night on 21 and 23 January. Ashfall was reported in areas to the SW on 23 January.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


14 January-20 January 2009

The IG reported that during 13 and 15-16 January steam-and-ash plumes from Tungurahua rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted W and NW; cloud cover often prevented visual observations on the other days during 14-20 January. Ashfall was reported, almost daily, in areas to the N, W, and SW. Roaring and explosions were occasionally reported. Incandescence in the crater was noted at night on 15, 18, and 19 January. On 16 January, a small lahar descended a drainage to the S. On 19 January, fumaroles in the crater were observed.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 January-13 January 2009

The IG reported that during 7-10 and 12 January steam-and-ash plumes from Tungurahua rose to altitudes of 6-6.5 km (19,700-21,300 ft) a.s.l. and drifted NW, WNW, W, and E. On most days, ash fell within 8 km NW and SW, and roaring, explosions, and "cannon shot" noises were reported. On 7 and 10 January, incandescence blocks ejected from the crater rolled down the flanks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


31 December-6 January 2009

The IG reported that during 31 December-6 January ash plumes from Tungurahua rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted SW, W, and NW. Ashfall was reported in areas downwind during 31 December-3 January; ashfall was heavy in Choglontus (W) on 2 January. Roaring, explosions, and "cannon shot" noises were reported almost daily, and large windows vibrated on 1, 3, and 4 January. During 2-4 January, incandescence at the summit was noted and blocks rolled up to 800 m down the flanks. Strombolian activity occurred at the summit on 4 January.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 December-30 December 2008

The IG reported that during 23 and 25-29 December ash plumes from Tungurahua rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. and drifted mostly S, SW, W, and NW. On 23 December incandescent material rolled down Tungurahua's flanks and a possible pyroclastic flow traveled 700 m down the NW flank. Ashfall was reported and explosions vibrated windows and the ground in areas to the SW. During 24-29 December roaring and "cannon shot" noises were reported almost daily; windows and the ground vibrated on 24, 28, and 30 December. A lahar traveled SW down the Mapayacu ravine on 27 December. Incandescence at the summit and ashfall in areas downwind were noted on 25, 26, 28, and 29 December. Explosions ejected blocks that rolled 500 m down the flanks on 25 December, 1500 m on 29 December, and 800 m on 30 December. On 30 December heavy black ash fell in areas to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 December-23 December 2008

The IG reported that during 17-23 December steam-and-ash plumes from Tungurahua rose to altitudes of 6-11 km (19,700-36,100 ft) a.s.l. and drifted in multiple directions. Roaring noises were reported daily and ash fell in areas downwind (mostly to the SW) during 18-21 December. Nighttime incandescence was noted during 17 and 21-23 December. On 21 December, explosions vibrated the ground. The following day sounds resembling rolling blocks were reported, and incandescent blocks traveled 500 m down the flanks. On 23 December vibrations rattled windows in Guadalupe, about 11 km N.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 December-16 December 2008

The IG reported that activity from Tungurahua on 15 December was characterized by increased seismicity, ash emissions, and the ejection of incandescent blocks. Ash plumes rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted NE. Ashfall was reported 6 km NNE in Runtún. Observers at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N, saw incandescent blocks ejected from the summit fall onto the W flank. Later that night, ash plumes rose to altitudes of 7 km (23,000 ft) a.s.l. and incandescence was seen at the summit. Emissions with variable ash content were seen on 16 December.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 December-9 December 2008

The IG reported that on 4 December an ash plume from Tungurahua rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted E. Light ashfall was reported in Runtún (6 km NNE) and Pondoa (about 8 km N). Cloud cover prevented visual observations during 5-9 December.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 November-2 December 2008

The IG reported that multiple lahars descended the S, NW, N, and NNE flanks of Tungurahua on 25 November. A landslide into the Puela River (to the S) reduced the flow volume by narrowing the river's channel. Lahars in the Vazcún River (to the N) dragged blocks up to 3 m in diameter. During 28-29 November, fumarolic activity originated from the NE and NW areas of the crater.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 November-25 November 2008

The IG reported that inclement weather mostly prevented observations of Tungurahua from 19-23 November; small fumarolic plumes were noted on 19 November. Roaring noises were reported on 20 November. On 22 November small lahars traveled down the Juive drainage (NNW flank), and on 25 November small lahars traveled down drainages on the W flank.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


5 November-11 November 2008

The IG reported little observed activity from Tungurahua during 5-11 November. Light ashfall was reported in Pillate (8 km W) and part of Riobamba (about 30 km S) on 4 November. Fumarolic activity was weak on 7 November and present on the NW edge of the crater on 8 November.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 October-4 November 2008

The IG reported that inclement weather mostly prevented observations of Tungurahua from 28 October to 4 November; steam plumes were noted on 2 November. On 28 October a lahar lasting about 30 minutes descended the Vascún River to the N. Lahars caused by rain descended multiple drainages on 1 November. Blocks about 50-70 cm in diameter were reported in Juive, (about 7 km NNW), La Pampas, (about 6 km S), and Bilbao (about 8 km N). Rolling blocks up to 1 m in diameter were reported in the SW. Residents bordering the Vascún River temporarily evacuated and then returned to their homes after the rain stopped.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 October-28 October 2008

The IG reported that inclement weather mostly prevented observations of Tungurahua during 22-28 October; fumarolic activity was noted on 22 October. On 23 October muddy waters descended the Vascún River to the N, causing a landslide and a ruptured water pipe that serviced Baños.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 October-21 October 2008

The IG reported that multiple lahars and mudflows descended drainages around Tungurahua on 14 October. A majority of the lahars traveled down drainages in the Pampas sector to the S, carrying blocks an average of 30-40 cm in diameter and up to 2 m in diameter. Other lahars and small mudflows descended drainages to the NW and W. On 19 October a small lahar descended the Bilbao drainage to the W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 September-23 September 2008

The IG reported that fumarolic activity from Tungurahua was observed during 19-20 September. During 21-22 September, small mudflows and sediment-laden waters descended drainages on the W and NW flanks. A lahar 50 cm thick was reported in the Pampas sector to the S.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 September-9 September 2008

The IG reported that clouds mostly prevented visual observations of Tungurahua during 3-9 September. On 3 September, a small lahar carried blocks down river drainages to the NW. Steam plumes rose 200 m above the crater on 6 September. On 8 September, a lahar descended a drainage to the S and carried blocks up to 50 cm in diameter.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 August-26 August 2008

The IG reported that on 19 August fumarolic plumes from Tungurahua rose 20 m above the NE crater and on 20 August, steam-and-ash plumes rose about 50 m above the crater. On 21 August, intense rains prompted the Tungurahua Observatory (OVT) to issue a warning of potential lahars in the Vascún river. A natural dam in the river was previously identified as potentially hazardous. On 23 August, a person in El Salado detected vibrations. The dam ruptured and material descended the Vascún river to the N at speeds of 10-15 m/s, destroying a house, damaging and demolishing bridges, and destroying multiple public swimming pools in the Baños area. Two people were injured and two people were missing.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 August-12 August 2008

The IG reported that during 6-8 August, explosions from Tungurahua were detected by the seismic network. Although clouds mostly prevented visual observations, steam-and-ash plumes were observed; on 6 August, ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted W. Ashfall was reported in areas to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 July-5 August 2008

The IG reported that during 30-31 July and 2-5 August, explosions from Tungurahua were detected by the seismic network. Although clouds occasionally prevented visual observations, ash plumes were observed that rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. and drifted NW, W, and SW. On 30 July, explosions and noises resembling blocks rolling down the flanks were reported. Incandescence at the crater was noted on 31 July. On 31 July and 3 and 4 August blocks rolled up to 1 km down the flanks and ashfall was reported in areas to the SW and W. During 3-4 August, roaring noises were reported in multiple areas. On 4 August an explosion produced an ash plume that rose to an altitude of 13 km (42,700 ft) a.s.l. Intense ashfall was reported in areas W. The noise generated by the explosion was heard as far away as Ambato, 31 km NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 July-29 July 2008

The IG reported that during 22-23 July, explosions from Tungurahua were detected by the seismic network. An ash plume rose to an altitude of 9 km (29,500 ft) a.s.l. On 25 July, lahars descended two drainages on the W flank. On 26 July, ash-and-steam plumes drifted NW and SW, and explosions and roaring noises were reported. Nighttime incandescence from the crater was noted. On 27 July, roaring noises accompanied ash plumes that rose to altitudes of 8-10 km (26,200-32,800 ft) a.s.l. Ashfall was reported in areas to the SW. During 27-29 July, incandescence was seen around the crater and blocks rolled 800 m down the flanks. Noises were reported and explosions caused windows to vibrate. Ashfall was reported in areas to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 July-22 July 2008

The IG reported that during 15-22 July, explosions from Tungurahua were detected by the seismic network. Although clouds occasionally inhibited visual observations, steam and ash-and-steam plumes were spotted and rose to altitudes of 7-10 km (23,000-32,800 ft) a.s.l. and drifted W and SW. On 19 and 22 July, nighttime incandescence from the crater was observed. On 20 July, lahars descended NW and S drainages. Ashfall was reported in areas downwind during 19-22 July. On 21 and 22 July, explosions vibrated windows in areas NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 July-15 July 2008

Ongoing ash emissions reported by the Washington VAAC during 9-15 July were based on pilot reports and continuing seismicity. Meteorological clouds prevented satellite observations of the plume near the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


2 July-8 July 2008

IG reported that during 1-7 July, explosions from Tungurahua were detected by the seismic network. Cloud cover inhibited visual observations during most days. On 1 July, an ash plume rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted W. During 4-6 July, explosions were heard. On 6 July, ashfall was reported in areas to the W and NW and incandescent blocks rolled 500 m down the flanks. On 7 July, explosions rattled windows in areas to the W, NW, and NE; ashfall was reported to the W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 June-1 July 2008

Although clouds occasionally inhibited visual observations, IG reported that during 25-27 June, steam and ash-and-steam plumes from Tungurahua rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted W and N. Incandescence from inside the crater was observed at night. On 29 June, an explosion generated a "cannon shot" noise and roaring, and caused windows to vibrate in Cusúa, about 7 km NW. More explosions were felt later that day. On 30 June and 1 July, slight ashfall was reported in the town of Manzano, about 8 km SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 June-24 June 2008

The IG reported that during 18-19 June, ash-and-steam plumes from Tungurahua rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. and drifted W, NW, and N. On 18 June, a small explosion was detected by the seismic network, and sounds of blocks rolling down the flanks, roaring noises, and "cannon shots" were reported. On 19 June, ashfall was reported in areas NW and W; in Cotaló, about 8 km NW, ash deposits measured about 2 mm thick. Incandescent material and blocks were ejected 500 m above the summit. Blocks rolled about 1 km down the flanks and roaring noises were reported. On 20 June, clouds inhibited visual observations of the summit. Lahars descended NW, W, and S drainages. A mudflow that traveled SW towards the Puela river carried blocks up to 80 cm in diameter.

On 21 June, two periods of increased seismicity were accompanied by strong ash emissions. The resultant ash plumes rose to altitudes of 8-11 km (26,200-36,100 ft) a.s.l. and drifted W. Intense ashfall was reported in areas within 8 km W and SW of the crater. On 22 June, lahars descended several drainages on the W and S flanks. Steam plumes with small ash content rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted W. Roaring noises vibrated windows in areas to the W. During 23-24 June, seismicity decreased and visual observations were inhibited by clouds.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 June-17 June 2008

The IG reported that although visual observations were occasionally limited due to cloud cover during 12-15 June, ash-and-steam plumes from Tungurahua were spotted that rose to altitudes less than 6 km (19,700 ft) a.s.l. Ash plumes drifted W and NE and ashfall was reported during 13-15 June in areas within 8 km W and SW. On 15 June, lahars descended NW and S drainages and resulted in a road closure in the Pampas sector to the S. A small lahar descended the Palitahua drainage on 16 June.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 June-10 June 2008

IG reported that on 2 June, two small explosions from Tungurahua were detected by the seismic network and ashfall was reported in areas on the SW flank. During 3-9 June, both activity at the summit and seismicity declined significantly. Ash-and-steam plumes rose to an altitude of 5.2 km (17,100 ft) a.s.l. during 4-5 June and drifted W and SW. A steam plume was visible on 8 June. Cloudy weather inhibited visual observations on other days during 3-10 June.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 May-3 June 2008

On 29 May, IG reported that activity from Tungurahua had gradually increased during the previous few weeks. On 23 May, a marked increase in the number of explosions and the intensity and frequency of ash plumes and ashfall was noted. Although visual observations were mostly limited due to cloud cover during 28 May-2 June, steam and ash-and-steam plumes were spotted and rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. Ashfall was reported in areas downwind. On 29 May, seismicity increased; several episodes of seismic tremor were detected. Two episodes were accompanied by roaring noises, ash emissions, and incandescent blocks that were ejected from the summit and rolled down the flanks. A thermal anomaly was detected in satellite imagery. Pyroclastic flows descended the N and NW flanks; deposits were observed the next day. On 30 May, emissions of plumes with low ash content were constant and roaring noises were reported. Slight roaring noises were reported on 1 and 3 June.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 May-27 May 2008

The IG reported that although visual observations were occasionally limited due to cloud cover during 21-27 May, ash and ash-and-steam plumes, often generated by explosions from Tungurahua, were spotted and rose to altitudes of 5.8-9 km (19,000-29,500 ft) a.s.l. Ash plumes drifted SW, W, and NW and ashfall was reported daily in areas within 8 km downwind. Roaring noises, "cannon shot" noises, and sounds resembling blocks rolling down the flanks were reported. On 22, 25, 26, and 27 May, windows vibrated in nearby areas, including at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N. On 23 May, incandescence at the summit was seen at night. On 27 May, lahars descended a drainage in the Pampas sector to the S.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


14 May-20 May 2008

The IG reported that although visual observations were occasionally limited due to cloud cover during 14-20 May, ash and steam plumes from Tungurahua were spotted most days and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. Ashfall was reported in areas within 8 km to the SW and W during 14-15 and 17-18 May. On 15 May, Strombolian activity was observed and blocks rolled down the flanks. On 17 and 18 May, "cannon shots" and explosions vibrated large windows in areas to the SW and W. Roaring noises were occasionally heard. On 18 May, a lahar possibly descended a drainage to the W. On 19 May, numerous incandescent blocks rolled about 1.6 km down the flanks following a large explosion. Roaring and "cannon shot" noises were audible and windows vibrated in nearby areas after the large explosion and several others that followed throughout the night. Ashfall was reported in areas W and NW during 19-20 May.

Based on information from IG, the Washington VAAC reported that on 20 May an ash plume rose to an altitude of 7.9 km (26,000 ft) a.s.l. and drifted NW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 May-13 May 2008

The IG reported that although visual observations were occasionally limited due to cloud cover during 7-13 May, ash and steam plumes from Tungurahua were spotted most days and rose to altitudes of 5-8 km (16,400-26,200 ft) a.s.l. Ashfall was reported in areas within 8 km to the SW, W, N, and NW on 6, 10, and 11 May. On 8 May, muddy waters were reported in areas SW and S and roaring noises were audible. On 11 May, incandescence at the summit was reported along with roaring noises and blocks that rolled 1 km down the flanks. After an explosion on 12 May, windows vibrated, roaring noises were again reported, and rockfalls occurred in an area 8 km S.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 April-6 May 2008

The IG reported that although visual observations were occasionally limited due to cloud cover during 29 April-6 May, ash-and-steam plumes from Tungurahua were spotted and generally rose to altitudes of 5.5-7 km (18,000-23,000 ft) a.s.l. Ashfall was reported in areas to the SW and W during 29 April-1 May and on 4 May. On 30 April, explosions produced steam-and-ash plumes to altitudes of 9-10 km (29,500-32,800 ft) a.s.l. Incandescence at the summit was visible and incandescent blocks rolled down the flanks. Roaring noises were audible. On 1 May, explosions were accompanied by "cannon shots" and intense incandescence at the summit. Windows vibrated in areas 6 km NE. Incandescent blocks rolled 1 km down the flanks. On 3 May, a small lahar descended the W flank.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 April-29 April 2008

The IG reported that although visual observations were occasionally limited due to cloud cover during 22-28 April, ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. Ashfall was reported in areas downwind on 23, 25, and 28 April. On 22 April, a small lahar descended the Mapayacu drainage to the SW. On 23 April, explosions accompanied by "cannon shot" noises produced ash plumes that drifted WSW and caused windows to rattle in areas to the NW, W, and SW. Blocks rolled 600 m down the flanks. On 25 April, fumarolic activity was noted on the interior of the NE crater rim. Sounds resembling blocks rolling down the flanks were reported.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 April-22 April 2008

The IG reported that although visual observations were mostly limited due to cloud cover during 16-22 April, ash-and-steam plumes from Tungurahua were spotted on 16, 20, and 21 April and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. Strombolian activity at the crater was noted at night on 15 and 20 April. During 16-19 April, explosions were registered by the seismic network. Ash plumes drifted W and SW; ashfall was reported in areas downwind during 19, 20, and 21 April. On 21 April a lahar disrupted the Ambato-Baños route for a few hours.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 April-15 April 2008

The IG reported that although visual observations were occasionally limited due to cloud cover, ash and ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 6-9 km (19,700-30,000 ft) a.s.l. during 9-15 April. Ash plumes drifted NW, W, and SW; ashfall was reported in areas downwind on 9, 11, and 14 April. Roaring noises were reported almost daily. On 9 April, lahars descended S and NW drainages and disrupted the access road to Baños. During the night on 11 April, incandescent material was present at the summit and rolled about 600 m down the flanks. On 12 April, lahars descended NW and SW drainages. On 13 April, a mudflow traveled NW down the Mandur drainage. During 14-15 April, Strombolian activity at the summit was noted.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 April-8 April 2008

The IG reported that although visual observations were limited due to cloud cover, ash and ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 5.5-9 km (18,000-30,000 ft) a.s.l. during 2-8 April. Ash plumes drifted in almost all directions; ashfall was reported in areas downwind during 4-8 April. Explosions were occasionally registered by the seismic network and roaring and "cannon shot" noises were reported. Incandescent material rolled 0.5-1 km down the flanks during 2-4 and 6-7 April and Strombolian activity at the summit was noted during 3-4 April.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 March-1 April 2008

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. during 25 March-1 April. Ash plumes drifted SW, W, and NW and were intermittently produced by explosions; ashfall was reported in areas downwind during 25 and 27-28 March. On 25 March, explosions propelled incandescent blocks from the summit that fell onto the flanks. Explosions also vibrated doors and windows in areas as far as 13 km away on 26 March and produced an ash plume to an altitude of 4 km (13,100 ft) a.s.l. on 27 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 March-25 March 2008

IG reported that although visual observations were limited due to cloud cover, ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 5.5-8 km (18,000-26,200 ft) a.s.l. during 19-25 March. Ash plumes drifted S, SW, W, NNW, and NNE; ashfall was reported in areas downwind during 19-21 and 23-25 March. Roaring noises were reported on 23 March. During 24-25 March, small explosions were registered by the seismic network.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 March-18 March 2008

IG reported that although visual observations were very limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua were spotted and rose to altitudes of 5.2-7 km (17,100-23,000 ft) a.s.l. during 12-18 March. Ash plumes drifted SW, W, NW, NE, and E; ashfall was reported in areas downwind (SW, W, and NW) on 13, 14, 16, and 18 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


5 March-11 March 2008

IG reported that although visual observations were very limited due to cloud cover, ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 5.5-8 km (18,000-26,200 ft) a.s.l. during 4-11 March. Incandescence at the summit was observed at night during 4-6 March. Ash plumes drifted W, SW, S, SE, E, and NE; ashfall was reported in areas downwind on 5, 6, and 10 March. Lahars descended drainages to the W and in the Pampas sector to the S on 6 and 8 March. On 8 March, lahars mobilized blocks up to 3 m in diameter. Very active fumaroles near the crater were spotted on 11 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 February-4 March 2008

IG reported that although visual observations were very limited due to cloud cover, steam and ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 5.8-8 km (19,000-26,200 ft) a.s.l. during 27 February-1 March. Ash plumes drifted NW, W, SW, and SE, ashfall was reported in areas to the SW on 27 February. Lahars or mudflows descended the Mapayacu and Choglontus drainages in the SW, and drainages in the Pampas sector to the S on 27 and 28 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 February-26 February 2008

IG reported that although visual observations were very limited due to storm cloud cover, gas-and-steam and ash-and-steam plumes from Tungurahua were spotted and rose to altitudes of 5.5-7 km (18,000-23,000 ft) a.s.l. during 20-26 February. Ash plumes drifted mainly W and SW and ashfall was reported in areas downwind on 19, 23, and 26 February. Lahars or mudflows affected roads in the Pampas sector to the S on 19, 20, and 25 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 February-19 February 2008

IG reported that although visual observations were limited due to cloud cover, ash and steam-and-ash plumes from Tungurahua were spotted and rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. during 12-19 February. Ash plumes drifted mainly NW, W, and NE, and ashfall was reported in areas downwind. Roaring noises were occasionally heard. During 12-13 and 16 February, incandescence at the summit was observed. Noises resembling blocks rolling down the flanks were heard on 14 and 17 February. On 18 February, a lahar descended the Achupashal drainage to the NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 February-12 February 2008

On 6 February, IG reported that pyroclastic flows from Tungurahua descended multiple NW and W drainages and tephra fall 3 cm in diameter was reported in areas to the SW. Based on information from the IG and satellite imagery evaluation, the Washington VAAC reported that ash plumes rose to estimated altitudes of 7.3-14.3 km (24,000-47,000 ft) a.s.l. and drifted S and NW. Ashfall was reported in areas downwind and to the SW and W, including Riobamba (30 km S). Precursory seismicity saturated local stations and presented similar patterns seen prior to intense episodes in July and August 2006. According to news articles, several hundred to 2,000 people were evacuated.

On 7 February, ash plumes rose to altitudes of 7-10 km (23,000-32,800 ft) a.s.l. and drifted mainly NW. Ash and tephra fell in areas to the SW and W. Strong roaring noises, explosions, and "cannon shots" were heard and windows vibrated, as far away as the Tungurahua Observatory (OVT) in Guadalupe, about 13 km NW. Incandescent material was propelled from the summit and fell on the flanks at about 3.5 km elevation, below the crater. Pyroclastic flows were detected in the Chontapamba ravine to the W and in the Juive and Mandur drainages to the NW. According to news articles, residents were evacuated again, hours after being allowed to return home.

During 8-11 February, ash plumes rose to altitudes of 6-10 km (19,700-32,800 ft) a.s.l. and drifted mainly W and E (on 10 February, only). Ashfall was reported from areas to the NW, W, and SW and was 3-4 mm thick in Choglontus to the SW on 8 February. Incandescence at the summit was also observed on 8 February. Ground vibrations were reported all four days. On 11 February, Strombolian activity was seen at the summit and material that was propelled out rolled 1.2 km down the flanks.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Reuters, Reuters


30 January-5 February 2008

IG reported that although visual observations were limited due to cloud cover, ash plumes were spotted and rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. during 30 January-5 February. Ash plumes drifted mainly W, NW, and E, and ashfall was also reported in areas to the SW, N, and NE. Roaring noises and "cannon shots" were heard almost everyday and the seismic network detected between 65-208 explosions daily.

On 30 January, incandescence at the summit was observed at night and incandescent blocks that were propelled from the summit by explosions rolled 600 m down the W flank. Explosions rattled windows as far away as the Tungurahua Observatory (OVT) in Guadalupe, about 13 km NW. A lahar descended the Mandur drainage, to the NW. On 1 and 4 February, incandescence at the summit was again noted and incandescent blocks traveled down the flanks. On 4 February, heavy ashfall to the SW was reported and explosions rattled windows in near-by areas. On 5 February, ashfall was reported in areas to the NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 January-29 January 2008

IG reported that although visual observations were occasionally limited due to cloud cover, ash plumes were spotted and rose to altitudes of 5.5-9 km (18,000-29,500 ft) a.s.l. during 23-29 January. Ashfall was reported daily in areas mainly within 10 km to the SW, W, NW, and NE. On 24 January, ashfall was reported from San Juan, about 40 km WSW and from Bilbao, 8 km W, where the ashfall was 2 mm thick. On 25 January, ashfall was reported in Riobamba, 30 km S.

During 22-25, 27, and 29 January, incandescence at the summit was observed at night and incandescent blocks that were propelled from the summit by explosions rolled 500-800 m down the flanks. Roaring noises and "cannon shots" were heard almost daily during 23-29 January. Lahars descend multiple drainages on 29 January and blocked the road to Baños in the La Pampas sector to the S.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 January-22 January 2008

IG reported that although visual observations were occasionally limited due to cloud cover, ash plumes were spotted and rose to altitudes of 5.5-9 km (18,000-29,500 ft) a.s.l. during 16-22 January. Ashfall was reported daily in areas mainly to the W, SW, and NW, and was heavy on 20 January. Roaring noises and "cannon shots" were heard frequently and windows and floors vibrated on 15, 20, and 21 January, as far away as the Tungurahua Observatory (OVT) in Guadalupe, about 13 km NW. On 16 January, incandescent blocks were propelled 200 m above the crater during a Strombolian eruption phase and blocks rolled 1 km down the flank. Three explosions produced blocks that rolled 2 km down the flanks. A small pyroclastic flow traveled 400 m down the NW side of the crater. Incandescence at the crater was again noted on 17 and 21 January.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 January-15 January 2008

IG released a special report on 9 January noting that increased seismic activity at Tungurahua was comparable to that of the few days prior to the eruption of 14 July, 2006.

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes were observed and rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. during 9-15 January. Ashfall was reported almost daily in areas to the NE, N, NW, W, and SW. Roaring noises and "cannon shots" were heard daily and windows and floors vibrated on 9, 10, 12, and 15 January, as far away as the Tungurahua Observatory (OVT) in Guadalupe, about 13 km NW. Incandescence at the summit was observed and incandescent blocks rolled 0.5-1 km down the flanks. On 11 January, Strombolian activity at the summit crater was observed and blocks rolled 600 m down the flank.

According to news articles, residents from two provinces continued to evacuate at night and about 20,000 health masks were distributed to residents from Baños and Quero.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Pan American Health Organization


2 January-8 January 2008

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua were seen and rose to altitudes of 5.5-8 km (18,000-26,200 ft) a.s.l. during 2-8 January. Plumes drifted NW and W. Ashfall was reported in areas to the W and SW during 3-4 and 7-8 January.

On 1 January, ash emissions were continuous and incandescent blocks rolled down the flanks. Roaring noises and "cannon shots" were heard, and the ground and windows vibrated in areas to the NNE and NNW. On 3 January, the seismic network recorded a high number of explosions. Some explosions caused acoustic waves similar to "cannon shots" that vibrated windows in areas to the W and NW. These explosions ejected incandescent blocks from the summit crater that rolled 500 m down the flanks. On 4 January, "cannon shots" were again noted as far as 13 km away; this caused large windows to vibrate in areas to the W and glass to break in Puñapí. Explosions vibrated the ground in one town and generated ash plumes that rose to an altitude less that 6 km (19,700 ft) a.s.l. During 5-8 January, roaring noises and "cannon shots" continued; windows and floors vibrated as far as the Tungurahua Observatory (OVT) in Guadalupe, about 13 km NW, on 6 January.

According to news articles, nearly 1,000 people were evacuated on 6 January to spend the night in evacuation shelters. They were allowed to return to their villages in the daytime to tend to homes, crops, and animals.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Associated Press


26 December-1 January 2008

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua were seen and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. during 25 December-1 January. Plumes drifted predominantly W and ashfall was reported in areas downwind and to the SW and N. Roaring noises and "cannon shots" were heard almost daily and windows and floors vibrated on 26, 27, and 30 December. During 26-27 December, incandescent blocks rolled down the flanks as far as 500 m. On 29 December, incandescent material observed at the summit was associated with explosive events. Incandescent blocks rolled 700 m down the NW flank on 29 December and 1,200 m down the flanks on 30 December. Incandescence at the summit was noted again on 31 December during the night.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 December-25 December 2007

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua were observed and rose to altitudes of 6-8.5 km (19,700-28,000 ft) a.s.l. during 19-25 December. Plumes drifted SE, SW, and WNW. Ashfall was reported in areas to the SW, W, NW, and N. Roaring noises and "cannon shots" were heard almost daily and windows and floors vibrated on 19, 21, and 23-24 December. On 19, 22, and 23 December, incandescent blocks were seen rolling hundreds of m down the flanks. Sounds indicating rolling blocks on the flanks were reported during 20-22 December, but were not observed due to cloud cover.

According to news articles, nearly 1,200 people in Penipe were evacuated nightly by security and specific communities around the volcano remained at an Orange Alert level.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Associated Press


12 December-18 December 2007

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. during 11-18 December. Roaring noises and "cannon shots" were heard. During 10-11 December, seismic signal interpretation was characterized by explosions and almost constant emission of ash plumes. Incandescent blocks were expelled from the summit and rolled down the flanks. On 11 December, explosions vibrated windows and the ground in areas near the volcano. During 10-14 December, ashfall was reported from areas downwind, including areas to the SW, W, and NW, and was almost constant during 10-12 December. On 13 December, incandescent blocks rolled down the flanks. Noises indicating blocks rolling down the flanks were heard on 15 December, but were not observed due to cloud cover.

During 16-18 December, explosions rattled windows in areas around the volcano, including Tungurahua Observatory (OVT) in Guadalupe, 11 km N, on 16 December. Ash plumes drifted SW. On 18 December, a steam plume rose to an altitude of 8.5 km (27,900 ft) a.s.l. and drifted NE. Constant steam-and-ash plumes were observed during an overflight. Ashfall was reported in areas to the NE. Based on pilot reports, observations of satellite imagery, and information from IG, the Washington VAAC reported that ash plumes rose to altitudes of 6.7-13.7 km (22,000-45,000 ft) a.s.l. and drifted E and NW on 18 December.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 December-11 December 2007

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. during 5-11 December. Plumes drifted SW, W, and NW. During 5-8 December, incandescence at the summit was observed and roaring noises and "cannon shots" were heard. During 6-7 December, incandescent material was propelled out of the crater and rolled about 1 km down the flanks. Explosions shook the ground and rattled windows in multiple areas, including at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N. During 5-8 December, ashfall was reported in areas to the SW, W, and NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 November-4 December 2007

IG reported that although visual observations were occasionally limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. during 27 November-4 December. During 28 November-1 December, seismic activity was elevated and multiple explosions were associated with almost continuous emissions of steam and ash. Explosions and "cannon shots" vibrated large windows and the ground within a 13 km radius of the summit on 28 and 29 November, and during 1-3 December. Ashfall was reported in areas to the SW, W, NW, N, and NE on 28 November, and 3-4 December. Incandescent blocks rolled 500-1000 m down the flanks on 28 November, 1 December, and 3 December. Roaring noises were occasionally reported.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 November-13 November 2007

IG reported that although visual observations were limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua rose to altitudes of 6-9 km (19,700-30,000 ft) a.s.l. during 7-13 November. Plumes mainly drifted W and SW and ashfall was reported from multiple areas downwind, including areas to the N and NW. Roars and "cannon shots" were also reported from several areas. A seismic station recorded a lahar on the SW flank that lasted about 30 minutes on 10 November. The next day, fumarolic activity on the NW edge of the crater rim was noted. Incandescent blocks propelled from the summit landed on the flanks and rolled a few hundred meters during 7-13 November. Incandescent blocks traveled 1 km down the flanks on 12 November.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


31 October-6 November 2007

IG reported that although visual observations were limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua rose to altitudes of 5.5-8 km (18,000-26,200 ft) a.s.l. during 31 October-6 November. Plumes drifted NNE, N, NW, W, and SW, and occasionally followed explosions. Ashfall was reported from areas downwind every day during the reporting period. On 31 October and 3 November, roars were heard. Incandescence and incandescent blocks at the summit were observed on 1, 2, and 5 November. On 4 November, the road to Baños in the La Pampas sector to the S was temporarily closed due to lahars.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 October-30 October 2007

IG reported that although visual observations were limited due to cloud cover, ash-and-steam and ash plumes from Tungurahua rose to altitudes of 5.5-6.5 km (18,000-21,300 ft) a.s.l. during 23-30 October. Plumes drifted E, SE, SW, W, and NW. On 25 October, ashfall was reported in areas on the SW flank. During 25-26 October, incandescence was observed at the summit and noises resembling "cannon shots," blocks rolling down the flanks, and roars were heard. On 28 October, ash plumes rose to 13 km (43,000 ft) a.s.l. During 28-29 October, noises resembling blocks rolling down the flanks and roars were again heard and ashfall was reported in areas to the NNE, N, and NNW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 October-23 October 2007

IG reported that ash plumes from Tungurahua, occasionally noted after explosions, rose to altitudes of 5.5-9 km (18,000-29,500 ft) a.s.l. during 17-23 October. Plumes drifted all directions, except to the E and SE. On 17 October, incandescent material propelled from the summit by explosions fell onto the flanks. A resultant ash plume drifted W. Fumarolic activity was noted on the NW flank. During 17-18 October, ashfall was reported from areas to the NW, N, and SW. On 19 October, lahars descended NW drainages and consequently the road between Ambato and Baños was closed.

During 20-21 October, explosions vibrated windows and doors in areas 8 km to the SW and N, including Tungurahua Observatory (OVT) in Guadalupe, 11 km N. On 21 October, incandescent material was ejected from the crater and roaring noises were heard. Ashfall was reported from areas to the SW on 21 October.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 October-16 October 2007

IG reported that ash plumes from Tungurahua rose to altitudes of 6.2-8 km (20,300-26,200 ft) a.s.l. during 10-16 October and drifted SW, W, NW, NE, and E. Clouds inhibited observations on 14 October. Ashfall was reported in areas to the SW, W, and NW during 9-12 and 15 October. During 11-12 October, incandescent blocks were ejected above the summit and descended 300 m down the W flank. Roaring noises were reported from multiple areas on 11, 13, and 14 October.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 October-9 October 2007

IG reported that ash plumes from Tungurahua rose to altitudes of 5-8 km (16,400-26,200 ft) a.s.l. during 2-9 October and drifted N, NW, W, E, and NE. Clouds inhibited observations on 7 and 9 October. Ashfall was reported in areas to the SW, NW, and N during 3-7 and 9 October.

Noises resembling blocks rolling down the flanks, roars, and "cannon shots" were heard during 3-9 October. On 9 October, a lahar with rocks up to 20 cm in diameter descended the Bilbao river valley.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 September-2 October 2007

IG reported that ash plumes from Tungurahua rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. during 26 September-2 October and drifted SW, W, and NW. Ashfall was reported in areas to the SW, W, NW, on all days except 26 September. Roaring and "cannon shot" noises were occasionally heard from multiple areas. On 28 September, blocks were ejected above the summit and descended 500 m down the flanks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 September-25 September 2007

IG reported that ash and steam-and-ash plumes from Tungurahua rose to altitudes of 5.3-7 km (17,400-23,000 ft) a.s.l. during 19-20 and 22-24 September and drifted SW, W, and NW. Ashfall was reported in areas to the SW and W on 20, 23, and 24 September. Roaring and "cannon shot" noises were occasionally heard from multiple areas. On 22 and 23 September, incandescent material was ejected above the summit and blocks descended 300 m and 500 m down the flanks, respectively. On 23 September, explosions rattled windows in areas W and SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 September-18 September 2007

IG reported that ash plumes from Tungurahua rose to altitudes of 5.5-8 km (18,000-26,200 ft) a.s.l. during 12, 14, and 16-18 September and drifted W and NW. Ashfall was reported in areas to the SW and W on 12, 14, 16, and 17 September. During 12-14 September, Strombolian activity was observed; incandescent material was ejected above the summit and blocks descended 100 m down the flanks. Roaring and "cannon shot" noises were heard from multiple areas. Strombolian activity was again observed on 16 September and explosions rattled windows at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N, on 17 September.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


5 September-11 September 2007

IG reported that ash plumes from Tungurahua rose to altitudes of 5.3-8 km (17,400-26,200 ft) a.s.l. during 5-6 and 9-10 September. A few explosions occurred on 7 September, in one case associated with incandescent blocks rolling down the flanks. On 8 September, a steam plume rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted W. During 9-10 September, incandescent blocks rolled about 100 m down the flanks. On 10 September, ashfall was reported in areas to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 August-4 September 2007

IG reported that ash plumes from Tungurahua rose to an altitude of 7 km (23,500 ft) a.s.l. on 29 August; clouds inhibited visual observations during 30 August-4 September. Ashfall was reported during 29 August-3 September in areas to the W. On 31 August, lahars were observed in drainages to the NNW and disrupted the road to Baños. Explosions rattled windows in Baños (8 km to the N) and at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N. On 1 September, ashfall was also reported from areas in the SW and NW. Incandescent blocks were propelled from the summit and observed from the OVT. Roars and "cannon shots" were heard during 29 August-1 September and 3 September. On 4 September, incandescence and rolling blocks on the E and N flanks were noted.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 August-28 August 2007

IG reported that ash plumes from Tungurahua rose to altitudes of 6-9 km (19,700-29,500 ft) a.s.l. during 22-28 August and drifted mainly NW, W, and SW. Noises resembling the sounds made by blocks rolling down the flanks were reported during 22-26 August and explosions rattled windows in surrounding areas, including Baños 8 km to the N, on 24 and 25 August. Ashfall was reported in nearby areas, especially to the NW, W, and SW, during 25-28 August. On 28 August, lahars affected W and NW drainages, the Pampas sector, and interrupted traffic on the route between Ambato and Baños. Incandescent blocks rolled down the flanks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 August-21 August 2007

Based on seismic interpretation, IG reported explosions and ash emissions from Tungurahua during 15-21 August. During 17-18 August, roaring and "cannon shot" noises were reported and ashfall occurred in areas to the W and SW. On 19 August, "cannon shot" noises were again reported and a gas-and-ash plume rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted W. Explosions on 20 and 21 August rattled windows at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N, and in houses in areas to the W. Ashfall was reported in areas to the SW on 21 August. Inclement weather inhibited visual observations on other days.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 August-14 August 2007

IG reported that during 8-9 August, steam-and-ash plumes from Tungurahua rose to a maximum altitude of 6 km (19,700 ft) a.s.l. and drifted W and SW. Ashfall was reported from areas SW and W on 8 August. Explosions on 9, 12, and 13 August sounded similar to "cannon shots" and vibrated windows in areas to the W and SW. Incandescent material was observed inside the crater and fell on the flanks. On 11 August, lahars traveled down NW drainages and disrupted the route between Ambato and Baños. Clouds obscured views during 10-12 August.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 August-7 August 2007

IG reported that on 1 August, ash-and-gas plumes from Tungurahua rose to altitudes of 5.5 km (18,000 ft) a.s.l. and drifted NW. Ashfall was reported from areas downwind. Noises indicating rolling blocks were heard. On 2 August, steam emissions and roaring noises were reported. On 5 August, roaring noises were reported and a steam-and-gas plume rose to an altitude of 5.1 km (16,700 ft) a.s.l. and drifted W. On 6 August, explosions were accompanied by roaring noises that were reported from the NW and SW sectors. A steam plume rose to an altitude of 5.2 km (17,100 ft) a.s.l. and drifted W on 7 August. Clouds occasionally inhibited visual observations.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 July-31 July 2007

As noted by the IG in their daily reports covering 25-31 July, Tungurahua emitted a substantial number of small ash-bearing explosions and several unusually large ones as well. Based on ground observer estimates, many plumes during the reporting interval rose to 2-3 km above the crater rim (up to ~1 mile above the crater) and dropped ash on towns located on the volcano's flanks.

On the 26th, the IG reported one of the larger explosions, the biggest since March 2007 (its seismic signal yielded a reduced displacement of 9.2 cm2). Associated ashfalls affected some parts of the volcano. The explosion took place at night and the plume height was not estimated.

On the 30th IG observers witnessed another strong explosion that generated a heavily ash-laden plume. The dense portion of the plume rose 400 m above the crater rim. A similar plume had not been seen since 16 August 2006. The associated column of less dense material rose to 3 km and visible portions of dense material appeared as a curtain of ash deposited to the W. Some blocks associated with the outburst rolled up to 0.5 km below the crater's rim. Visibility hampered further observations that day but the many emission noises included the hammering of bouncing blocks.

Tungurahua's 25-31 July activity spurred numerous VAAC reports, but satellite analysts generally had great difficulty with cloudy conditions and few if any plumes were clearly detected.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


18 July-24 July 2007

IG reported that during 18-24 July, intermittently visible ash plumes from Tungurahua rose to altitudes of 5.2-8 km (17,100-26,200 ft) a.s.l. and drifted NW, W, and SW. Ashfall was reported from areas SW and W during 19-21 and 24 July. On 20 July, mudflows were reported from drainages to the NW. On 21 July, a steam-and-gas plume drifted W. On 21, 22, and 24 July, ash plumes were occasionally accompanied by roaring sounds, "cannon shots", or noises that resembled blocks rolling down the flanks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 July-17 July 2007

IG reported that during 11-16 July, ash plumes intermittently visible from Tungurahua rose to altitudes of 5.3-7 km (17,400-23,000 ft) a.s.l. and drifted N and W. Ashfall was reported from areas SW during 11-12 and 14-16 July. On 13 July, roaring noises were heard and "cannon shots" rattled windows of houses in areas to the W. A steam plume rose to an altitude of 5.2 km (17,100 ft) a.s.l. and drifted W. On 14 July, fumaroles were spotted on the NW flank. On 15 July, lahars traveled down W and S drainages. Lahars in a NW drainage temporarily blocked a road. "Cannon shots" and roaring noises were heard during 15-16 July.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 July-10 July 2007

During 3-10 July, IG reported that ash plumes from Tungurahua rose to altitudes of 6-7.5 km (19,700-24,600 ft) a.s.l. and drifted mainly SW and W. Ashfall was reported from areas downwind during 4 and 6-9 July. Incandescence was visible at the crater on 4 and 9 July and noises were reported during 4-5, 7, and 10 July. On 8 July, incandescence was again seen at the summit and blocks rolled 500 m down the flanks. On 9 July, two explosions were accompanied by "cannon shots" that vibrated windows at the Tungurahua Observatory (OVT) in Guadalupe, 11 km N. Strombolian activity was observed and blocks rolled 1 km down the flanks. On 10 July, a lahar occurred in a W drainage.

Based on pilot reports, information from IG, and satellite imagery, the Washington VAAC reported that during 9-10 July, ash plumes rose to altitudes of 4.9-7 km (16,000-23,000 ft) a.s.l. and drifted W.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


27 June-3 July 2007

IG reported that on 27 June, ash plumes from Tungurahua rose to an altitude of 7.5 km (24,600 ft) a.s.l. and drifted NW, W, and SW. Ashfall was reported from areas to the SW. Observers from the NW reported reddish material at the summit. A lahar occurred in a NNW drainage. Roaring noises were reported during 27-28 June. On 2 July, ashfall was reported from areas to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 June-26 June 2007

The IG reported that during 20-25 June mudflows and lahars traveled on the S, W, NW, and N flanks of Tungurahua and interrupted traffic. A steam plume with little ash content was observed on 21 June. On 22 June, ashfall was reported SW in Choglontus and roaring noises were heard. A small landslide occurred on the edge of the Chambo river; another landslide affected a highway. On 23 June, a steam plume with little ash content rose to an altitude of 5.8 km (19,000 ft) a.s.l. and drifted W. The next day, ashfall was reported. During 23-24 June, roaring noises were heard.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 June-19 June 2007

The IG reported that heavy and occasionally continuous rains resulted in mudflows and lahars on the flanks of Tungurahua during 12 and 14-16 June. On 12 June, lahars in the Pampas sector disrupted traffic on the route between Ambato and Baños for several hours. Traffic was again disrupted on 14 June and lahars occurred in W and SW drainages. A potable water system in a locality to the SW was affected by one of the lahars. Slight ashfall was reported from Bilbao, about 8 km to the W. On 15 June, lahars traveled in NW, W, and SW drainages. Mudflows interrupted traffic on the route between Ambato and Baños and dragged blocks 1 m in diameter in the W-flank Mandur drainage. According to the Washington VAAC, IG reported that an ash plume rose to an altitude of 5 km (16,500 ft) a.s.l. and drifted WSW. Ash was not visible on satellite imagery. During 15-16 June, heavy rains led to a landslide in the Peras Pamba sector near Cusúa (8 km NW) that blocked the flow of the Chambo river for about 20 minutes. Mudflows continued to affect the Pampas sector on 16 June. On 18 June, an ash plume rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted W.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


6 June-12 June 2007

During 5-9 June, IG reported that minor ash plumes from Tungurahua rose to altitudes of no more than 5.5 km (18,000 ft) a.s.l. and drifted W. Ashfall was reported from areas WSW and NW on 6 June and roaring noises were reported during 5-6 and 9-10 June. Lahars transporting stones and wood were observed on the W flank in the Bilbao drainage on 6 June. Later that day, lahars were noted on the N flank in the Vazcún drainage. On 7 June, several mudflows affected W and NW drainages and in the Pampas sector, covered a highway with debris 1 m thick. On 8 June, multiple lahars again traveled in W and NW drainages. Lahars carried blocks 20-30 cm in diameter and interrupted traffic in the Pampas sector. Mudflows were abundant in Pama on 9 June.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 May-5 June 2007

During 30 May-5 June, IG reported that ash plumes intermittently visible from Tungurahua rose to altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted mainly SW, W, and NW. Ashfall was reported from areas downwind between 30 May and 3 June. Muddy waters traveled down W, SW, and NW drainages during 30 May-1 June. Lahars were reported from the Choglontus drainage to the WSW on 30 May and from the Motilones drainage to the WNW on 1 June. During 4-5 June, roaring noises were reported.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 May-29 May 2007

IG reported that during 23-29 May, steam and steam-and-ash plumes intermittently visible from Tungurahua rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. and drifted NW and W. Ashfall was reported from areas SW on 25 May, W and SW on 26 and 29 May, and NW on 27 May.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 May-22 May 2007

During 15-22 May, IG reported that ash plumes intermittently visible from Tungurahua rose to altitudes of 5.1-7 km (16,700-23,000 ft) a.s.l. and drifted mainly W, NW, and E. Ashfall was reported from areas SW and W during 16-17 May, SW on 19 May, and W and NW during 20-21 May. Lahars and muddy waters traveled down W, NW, and N ravines during 15 and 17-19 May and caused the road to Baños to close on 18 May. Lahars that traveled in the Bilbao sector and down NW ravines on 20 May blocked the Baños-Penipe highway and obstructed the route between Ambato and Baños for about 6 hours. Muddy waters traveled down ravines to the N.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 May-15 May 2007

During 9-12 and 14 May, IG reported that ash plumes were visible from Tungurahua and rose to an altitude of 5.1 km (16,700ft) a.s.l. during 11-12 May. Plumes drifted W and NW. Ashfall was reported on 9 May in areas about 8 km to the SW and W and trace ashfall was reported about 30 km NW in Ambato. Incandescence at the summit was noted that evening. Ashfall was also reported on 10, 11, and 14 May from areas NW, SW, and W; on 11 May, the ashfall was red in color. Lahars and muddy waters that traveled into the Pampas sector and in NW ravines blocked the Baños-Penipe highway during the morning of 10 May. Muddy waters traveled in W ravines on 12 May and SW ravines on 14 May.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 May-8 May 2007

IG reported that lahars and muddy waters that traveled into the Pampas sector and in W and NW ravines blocked the Baños - Penipe highway during parts of 3, 4, and 6 May. During 2-3 and 5-7 May, ash plumes from Tungurahua rose to altitudes of 5.2-7 km (17,100-23,000 ft) a.s.l. and drifted NW and W. Ashfall was reported in areas about 8 km to the SW and W during 3, 6, and 7 May. The Washington VAAC reported that a diffuse ash plume was visible on satellite imagery drifting W on 8 May. Clouds occasionally inhibited visual observations during the reporting period.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


25 April-1 May 2007

IG reported that during 25, 27-29 April, and 1 May, ash plumes from Tungurahua rose to altitudes of 5.8-7.5 km (19,000-24,600 ft) a.s.l. and drifted SW and W. Ashfall was reported in areas to the SW, W, and NW during 25, 29-30 April, and 1 May. On 25 April, muddy water flowed down river valleys to the NW and disrupted the road between Ambato and Baños. The next day, lahars traveled down almost all of the river valleys, but were most concentrated in valleys to the W. Lahars and muddy water flowed down NW and W river valleys on 27 and 30 April.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 April-24 April 2007

IG reported that during 17-18 April, Strombolian activity from Tungurahua was observed; incandescent material was ejected about 500 m above the summit and blocks descended down the flanks. Lahars carring large blocks NW down the Mandur gorge caused a road closing on 19 April. During 17-24 April, ash plumes rose to altitudes of 5.5-9 km (18,000-29,500 ft) a.s.l. and drifted W and N. Ashfall was reported from areas mainly to the N, NW, W, and SW during 17, 19, 21-22, and 24 April. On 23 April, lahars were observed in several gorges to the NW. Clouds occasionally inhibited views of the summit during the reporting period.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 April-17 April 2007

IG reported that based on visual observations and reports from pilots, ash plumes from Tungurahua rose to altitudes of 6.7-8 km (22,000-26,200 ft) a.s.l. and drifted NNW on 11 April. Fumarolic activity originated from the NE and E edges of the crater. During 12-17 April, ash plumes, occasionally accompanied by roaring, rose to altitudes of 5.8-8 km (19,000-26,200 ft) a.s.l. and drifted mainly W. Ashfall was reported from areas downwind on 12 April. During 13-14 April, Strombolian activity was observed; incandescent material was ejected about 200-300 m above the summit and blocks descended 500-800 m down the flanks. During 15-17 April, lahars descended several NW, W, and SW valleys. In the Pampas sector, lahars with blocks 50 cm in diameter disrupted the roads between Ambato and Baños, and between Baños and Penipe.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 April-10 April 2007

IG reported that during 3-5 April, ash plumes from Tungurahua rose to altitudes of 8-9 km (26,200-29,500 ft) a.s.l. and drifted NW and W. Ashfall was reported at areas to the SW on 4 April. On 3 April, blocks rolled 800 m down the W flank; noises indicating rolling blocks were heard on 5 and 6 April. Lahars descended the W flank on 6 April. During 6-8 April, ash plumes, occasionally accompanied by roaring noises and "cannon shots", rose to altitudes of 7-10.5 km (23,000-34,400 ft) a.s.l. and drifted mainly W and NW. Ashfall was reported from areas about 8 km NW and SW from the summit on 6 April. On 9 April, ashfall was reported from areas 8 km W. On 10 April an explosion occurred. Incandescence was seen at the summit and blocks rolled about 100 m down the flanks. Clouds occasionally inhibited visual observations during the reporting period.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 March-3 April 2007

IG reported that on 27 March, at 1716, an ash column from Tungurahua rose to an altitude of 11 km (36,000 ft) a.s.l. An accompanying pyroclastic flow traveled 1 km down the Mandur gorge on the NW flank. A lahar traveled W down the Bilbao gorge and vibrated near-by structures. On 28 March, ash plumes again rose to altitudes of 11 km (36,000 ft) a.s.l. Ashfall was reported from areas downwind. Noises that resembled rolling blocks down the flanks were reported. Hot steaming mudflows traveled N, NW, and W. On 29 March, three explosions rattled windows in areas as far away as 8 km. During 30 March-3 April, ash plumes, occasionally accompanied by roaring noises and "cannon shots," rose to altitudes of 6-10.5 km (19,700-34,400 ft) a.s.l. and drifted mainly W and NW. Incandescent material was ejected 300 m above the crater and subsequently descended about 1 m down the flank on 31 March; similar activity was observed at the summit during 1-2 April. Ashfall was reported from areas about 8 km SW, N, and W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 March-27 March 2007

IG reported that during 21-27 March, constant emissions of ash and steam from Tungurahua produced plumes that rose to altitudes of 7-10 km (23,000-32,800 ft) a.s.l. and drifted mainly W, NW, and N. Ashfall was reported from areas downwind and from areas SW within 8 km, on all days except 25 and 27 March. Noises resembling "cannon shots" and blocks rolling down the flanks were heard on 21, 22, and 25 March; windows rattled as far away as 11 km N in Guadalupe. On 23 March, lahars traveled mainly down NW gorges and affected the roads between Ambato and Baños, and between Baños and Penipe.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


14 March-20 March 2007

IG reported that during 14-20 March, explosions from Tungurahua were accompanied by noises that resembled "cannon shots." On 16, 18, and 20 March, explosions rattled windows at the observatory in Guadalupe, about 11 km N. Incandescent material was ejected 100-200 m above the summit on 14, 16, and 20 March and rolled 500-800 m down the flanks on 16,18, and 20 March. Ash plumes rose to altitudes of 6.5-12 km (21,300-39,400 ft) a.s.l. during the reporting period and drifted mainly NW and W. Ashfall was reported as far as Cotaló (13 km NW) on 16 March and from other areas S, W, and NW during 14-20 March. Rainfall contributed to lahars in valleys W and NW on 15 and 16 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 March-13 March 2007

IG reported that during 7-13 March, explosions from Tungurahua were accompanied by noises that resembled "cannon shots." Ash plumes rose to altitudes of 5.5-9 km (18,000-30,000 ft) a.s.l. and drifted NW and W. Ashfall was reported from areas downwind during 7-8 and 10-13 March. Incandescent material was ejected and rolled 300-500 m down the flanks during 7-10 and 12 March.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 February-6 March 2007

IG reported that noises produced by material rolling down the flanks of Tungurahua, roars, and "cannon shots" were heard during 28 February-6 March. Visual observations were limited due to cloud cover. Based on pilot reports, the Washington VAAC reported on 28 February that an ash plume rose to an altitude of 7.6 km (25,000 ft) a.s.l. and drifted W. On 1 and 2 March, gas-and-ash plumes rose to altitudes of 7-10 km (23,000-32,800 ft) a.s.l. and also drifted W. Incandescent material was ejected above the summit and rolled down the N and NW flanks. During 4-5 March, ash plumes rose to altitudes of 10-12 km (32,800-39,400 ft) a.s.l. and drifted W and NW. During 4-6 March, explosions rattled windows in Guadalupe, about 11 km N, and Baños, about 8 km N. Ashfall was reported from areas to the SW during the reporting period.

According to news articles, authorities conducted a voluntary evacuation of about 100 families on 5 March due to increased activity at Tungurahua.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Associated Press


21 February-27 February 2007

Volcanic tremor and long-period earthquakes from Tungurahua began at approximately 2100 on 23 February. On 24 February at 0310, tremor amplitude increased. Incandescent material was ejected 800 m above the summit and fell on the flanks about 1 km below the summit. An eruption plume drifted NW and roaring noises were audible. Gravel and sand-sized ash reportedly fell at Pillate (8 km W) and San Juan (40 km WSW) and in places accumulated up to 3 mm thick. Deposits of ash 2 mm thick were reported from Bilbao (8 km W), Cotaló (8 km NW), Manzano (8 km SW), and Choglontus (W).

On 25 February, 12 moderate to large explosions occurred according to seismic interpretation. Based on satellite imagery, MWO, pilot reports, and the IG, the Washington VAAC reported that ash plumes rose to altitudes of 7.6-12.2 km (25,000-40,000 ft) a.s.l. during 24-25 February. Plumes drifted SW and NW.

On 26 February, a plume with no ash content rose to 6 km (19,700 ft) a.s.l. and drifted W. Later that day, two explosions produced ash plumes that 7 km (23,000 ft) a.s.l. and again drifted W. On 27 February, incandescent material was ejected above the summit and fell on the flanks about 500 m down the flanks. Noises produced by material rolling down the flanks and "cannon shots" were heard during 25-27 February.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 February-13 February 2007

During 7-13 February, visual observations of Tungurahua were limited due to inclement weather. During 12-13 February, seismicity increased and fumarolic activity was observed from the N and NE flanks. ON 13 February, a plume with moderate ash content rose to an altitude of 7 km (23,000 ft) a.s.l. and drifted NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 January-30 January 2007

During 24-30 January, visual observations of Tungurahua were limited due to inclement weather. On 26 January, lahars affected the Pampas sector and blocked the Baños - Penipe highway until the next day. Lahars were also reported to the W in Bilbao, NNW in Mandur, and NW in la Hacienda. Small lahars to the W were reported on 28 January and a steam plume was visible on 29 January.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 January-9 January 2007

During 3-9 January, seismicity at Tungurahua remained low to moderate and visual observations were limited due to inclement weather.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 December-2 January 2007

During 27 December-2 January, seismicity at Tungurahua remained moderate to low and visual observations were limited due to inclement weather. On 27 and 28 December, lahars traveled down drainages including Bilbao to the W, Mandur to the NNW, and Mapayacu to the SW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 December-26 December 2006

On 21 December, IG reported that lahars from Tungurahua traveled NW down the Mandur gorge resulting in a road closing and W down the Bilbao gorge. Gas-and-steam emissions produced small plumes on 22, 23, and 25 December.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 December-19 December 2006

IG reported that during 13-19 December seismic activity from Tungurahua was minimal in intensity and duration. Steam plumes with possible light-ash content reached an altitude of 8 km (26,000 ft) a.s.l. on 13 December and between 5.8-6 km (19,000-19,700 ft) a.s.l. during 14-17 and 19 December. The plumes drifted in multiple directions. On 14 December, a lahar traveled SW down the Mapayacu gorge.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


6 December-12 December 2006

IG reported that during 6-12 December, emissions from Tungurahua produced steam plumes with little ash content that reached altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted in multiple directions. On 6 December, plumes reached an altitude of 10 km (32,800 ft) a.s.l. Ashfall was reported in areas including Cotaló, about 13 km NW, Pillate, about 7 km to the W, and Puela, about 8 km SW. On 9 December, ashfall up to 1 mm thick was reported about 12 km N in Baños.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 November-5 December 2006

IG reported that during 29 November-5 December, emissions from Tungurahua produced ash-and-steam plumes that reached altitudes of 6-7 km (19,700-23,000 ft) a.s.l. and drifted predominantly W and N. Observations on 3 December were hindered due to inclement weather.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 November-28 November 2006

IG reported that during 21-28 November, emissions from Tungurahua produced ash and steam plumes that reached altitudes of 6-9 km (19,700-29,500 ft) a.s.l. and drifted predominantly NW and W. Ashfall about 1 mm thick was reported from areas 8 km WSW on 21 November and from areas 8 km W on 25 November. During 26-27 November, Strombolian activity propelled incandescent material up to 600 m above the summit. Blocks rolled 2 km down the flanks. Lightning was visible in an ash plume that reached 7 km (23,000 ft) a.s.l. and ashfall was reported from areas 8 km WSW. On 27 November, an ash plume rose to 9 km (29,500 ft) a.s.l. and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 November-21 November 2006

IG reported that lahars from Tungurahua traveled NW down the gorges of Vazcún and Mandur on 14 and 15 November, respectively. During 16-19 November, emissions produced gas plumes with minor ash content that reached altitudes of 5.2-5.5 km (17,100-18,000 ft) a.s.l. On 17 November, an ash plume reached an altitude greater than 10 km (32,800 ft) a.s.l. and drifted NW and NE.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 November-14 November 2006

IG reported that during 7-12 November, emissions from Tungurahua produced ash plumes that reached altitudes of 6-9 km (19,700-29,500 ft) a.s.l. and drifted predominantly NE, NW, and W. On 7 November, a voluminous lahar traveled down gorges to the W and reached as far as the Chambo River, about 7 km from the summit. On 8 November, blocks expelled from the summit rolled down the flanks and ash fall was reported from areas including Casúa (7 km NW) and Baños (8 km NE). On 10, 11, and 13 November, ash fall was reported from areas including Penipe (8 km SW). During 12-13 November, lahars traveled down W and NW drainages and the Vazcún River swelled with muddy water.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 November-7 November 2006

IG reported that during 1-5 November, emissions from Tungurahua produced plumes consisting of steam, gas, and moderate ash that reached altitudes of 1-3 km (3,300-9,800 ft) a.s.l. and drifted in multiple directions. On 6 November, ash plumes rose to 6 km (19,700 ft) a.s.l. and drifted NW. Ashfall was reported from several towns downwind of the plumes on 5 and 6 November, including Bilbao (8 km W), Cotaló (13 km NW), and Manzano (8 km SW). On 2 November incandescent blocks were expelled from the summit and rolled about 700 m down the W and E flanks. Nighttime incandescence was observed during 2-4 November.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 October-31 October 2006

IG reported that during 25-30 October emissions from Tungurahua produced plumes consisting of steam, gas, and moderate ash that reached altitudes of 7-8 km (23,000-26,000 ft) a.s.l. and drifted W, SW, NW, and NE. Ashfall was reported from several towns downwind of the plumes including Penipe (8 km SW), Bilbao (8 km W), Cotaló (13 km NW), and Baños (8 km NNE). On 28 October, incandescent blocks were expelled from the summit and rolled about 500 m down the W and E flanks. The next day, a lahar traveled NNW down the Mandur drainage and muddy water swelled in the Vazcún drainage.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 October-24 October 2006

IG reported that during 18-19 October, emissions from Tungurahua increased in intensity and ash content and seismic tremor was continuous. During the night, lava fountains reached heights of 6 km (19,800 ft) a.s.l. and blocks rolled 800 m down the flanks. According to the Washington VAAC, a pilot reported an ash plume to an altitude of 8.5 km (28,000 ft) a.s.l. Ash plumes drifted NE and E and generated ashfall about 50 km E, in Puyo. According to news articles, about 300 villagers evacuated from the flanks. During 20-24 October, emissions continued and produced plumes to 7-8 km (23,000-26,000 ft) a.s.l. Ashfall was reported from towns on the N, NW, W, SW, and E flanks.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


11 October-17 October 2006

IG reported an increase in emissions and seismicity at Tungurahua on 11 and 12 October. Steam plumes with slight to moderate amounts of ash reached heights of 9-12 km (29,500-39,500 ft) a.s.l. and resulted in light ashfall in areas NW and W. During 13-17 October, seismicity decreased and emissions produced plumes that reached heights of 7-8 km (23,000-26,000 ft) a.s.l. On 16 October, a small lava flow produced incandescent blocks and gas plumes. Lahars traveled NNW and NNE down the gorges of Vazcún and Ulba, respectively. Incandescence from the crater could be seen during most of the reporting period.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 October-10 October 2006

During 4-5 October, fumaroles on the N flank of Tungurahua were active. Steam emissions with minor ash content rose to 1 km above the summit (or 19,800 ft a.s.l.) and drifted W. Additional steam plumes possibly originated from the recent lava-flow front. Incandescence was not observed.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 September-3 October 2006

No ash emissions from Tungurahua were reported by the IG between 27 September and 2 October. However, a slow-moving lava flow was seen moving down the NNW flank on 2 October. Some fumarolic activity from the crater was observed this week when the weather was clear. On 3 October an explosion sent an ash plume to a height of 5 km above the summit, about 10 km (6,200 ft) a.s.l. Ash fell in nearby communities to the W. Multiple sources that contributed to an aviation ash advisory that indicated a higher-level plume to 9.8 km (32,000 ft) a.s.l. extending E to a distance of 22 km.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


20 September-26 September 2006

During 20-26 September seismicity remained low, as Tungurahua continued to generate ash eruptions. Ash rose 2 km above summit (23,000 ft a.s.l.) on the afternoon of 21 September. Moderate ash emissions occurred again on 22 September. Three more ash emissions on 23 September caused ashfall in Penipe; one plume rose 3 km above the summit (26,000 ft a.s.l.), and another 4 km (29,500 ft a.s.l.). Ash plumes were seen again on 25 September.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


13 September-19 September 2006

During 13-19 September, seismicity at Tungurahua remained relatively low. Steam-and-gas plumes rose to a maximum height of 1 km above the summit (19,800 ft a.s.l.) and drifted predominantly W. Incandescence at the summit was observed at night.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 September-12 September 2006

During 6-12 September, seismicity at Tungurahua remained low and visual observations were limited due to inclement weather. On 7 September, lahars descended the NW gorges of Chontapamba and Mandur. On 8 and 9 September, steam-and-gas plumes with little to no ash content rose to ~100-500 m above the summit (~16,800-18,100 ft a.s.l.) and drifted NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 August-5 September 2006

During 30 August-5 September, seismicity at Tungurahua remained low. Steam and gas plumes with low to no ash content rose to 300-600 m above the summit (17,500-18,400 ft a.s.l.) and drifted NNW and W. On 1 September, lava flows on the NW flank were confirmed to have ceased. On 2 September, incandescence at the summit was observed.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 August-29 August 2006

During 23-27 August, visual observations of Tungurahua were impaired due to inclement weather. Based on seismic interpretation, lava continued to slowly flow NW towards Cusúa and La Hacienda. Seismicity was low and dominated by long-period earthquakes. Inclinometer measurements indicated no additional inflation on the flanks.

Several United Nations agencies and other organizations provided aid for an estimated 19,000 people that remained in shelters.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), ReliefWeb


16 August-22 August 2006

A large eruption of Tungurahua began on 16 August at 1900 and continued to 17 August at 0200, when activity began to diminish. According to the Instituto Geofísico, seismic activity increased on 16 August and clinometer measurements indicated a bulge on the N flank as compared to 11 August measurements. Ash-and-gas plumes reached heights of 3 km above the summit (26,300 ft a.s.l.) and drifted W and NW. About 3,200 people were evacuated from at-risk areas. On 17 August, about 20 pyroclastic flows traveled NW through the Achupashal, La Hacienda, and Mandur drainages, and NNW towards the Juive and Vazcún drainages. The Chambo and Puela rivers and several roads to the W and S were blocked by pyroclastic-flow debris. Tephra fall (3 cm in diameter) was reported from several areas in a zone that extended from Penipe in the SW to about 15 km NW. Ash plumes reached estimated heights of 10 km above the summit (49,000 ft a.s.l.) and covered the central part of Ecuador, forming a cloud ~742 km long and ~185 km wide trending NNW and SSE.

On 18 August, incandescent blocks were ejected from the summit and descended about 1.7 km down the flanks. Based on seismic interpretation, one of the blockages damming part of the Chambo River had been breached. During 18-19 August, the N flank continued to inflate. During 20-21 August, steam emissions were observed during breaks in the cloud cover and the N flank exhibited deflation. On 23 August, two lava flows were identified on the NW slope moving at a slow rate.

According to news reports, ash and debris fall caused fires and severe damage to five villages. An estimated 20,000 hectares (50,000 acres) of crops were destroyed. At least five people are dead or missing, and several more were injured. An estimated 4,000 people have been relocated to shelters.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Agence France-Presse (AFP), ReliefWeb, Associated Press, ReliefWeb


9 August-15 August 2006

During 9-15 August, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash that reached heights of ~1 km (~3,300 ft.) above the summit (~19,800 ft a.s.l.). Light ashfall was reported in nearby localities during 9-10 August. On 9 and 13 August, explosions expelled blocks of incandescent material that rolled 100 m down the W flank.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 August-8 August 2006

According to the Instituto Geofísico, on 1 August a pyroclastic flow from Tungurahua that traveled an unstated distance W left deposits an estimated 50 m thick consisting largely of blocks and ash. On 2 August, a small lahar that traveled NW caused the closing of a highway. Strombolian activity was observed at night on 3 August. Small explosions were registered during 3-7 August. On 6 August, light ash fall was reported ~8 km SW in the town of Manzano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 July-1 August 2006

On 26 July, the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) reported that, according to the Ecuadorian Civil Defense, approximately 13,000 people had been severely affected by the eruption of Tungurahua. About 815 remained in shelters.

During 26 July-1 August, eruption columns with small-to-moderate ash content reached an altitude of ~9 km (~30,000 ft) a.s.l. Ash fall was reported in Pillate, ~ 7 km to the W on 27-29 and 30 July, as far as Baños ~12 km N and Puela ~8 km S on 29 July and Cotaló ~13 km NW on 30 July. On 27 July, incandescent material from explosions descended ~1 km down the flanks. A thermal anomaly was observed on satellite imagery during the reporting period.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), ReliefWeb


19 July-25 July 2006

During 19-25 July, visual observations of Tungurahua were limited due to heavy cloud cover. Based on seismic interpretations, daily explosions recorded during the week were mostly small to moderate in intensity. Small pyroclastic flows descended NW a maximum distance of 1 km on 21 and 23 July. Steam-and-ash plumes were observed during 19-22 and 24 July and reached maximum heights of 5 km above the summit (32,900 ft a.s.l.) on 21 July. According to the Washington VAAC, pilots reported on 19, 22, and 23 July that ash plumes reached altitudes of 10.7 km (35,000 ft) a.s.l. and drifted predominantly W. A hot spot was visible on satellite imagery from 19 to 22 July.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 July-18 July 2006

During 12-18 July, eruptive activity at Tungurahua increased. Incandescent blocks rolled 500 m down the flanks and steam emissions with moderate ash content reached heights of 300 m above the crater (17,500 ft a.s.l.) during 11-13 July. On 14 July, a large eruption generated ash clouds that reached heights of 15 km above the summit (66,000 ft a.s.l.). The plume expanded in multiple directions and then drifted predominantly W, SW, and E. Ash accumulated to a maximum thickness of 15 mm in Pillate, about 7 km to the W. At least five pyroclastic flows, the first since 1999, traveled N and NW. The resulting deposits were up to 8 m thick and 20 m wide. At least four lava flows were also observed. Over 3,700 people from seven small villages near the volcano evacuated to nearby towns. On 15 and 16 July, multiple pyroclastic flows reached the area of Cusúa, approximately 7 km NW of the summit. Explosions and pyroclastic flows generated ash clouds that reached heights of 6 km above the volcano (36,200 ft a.s.l.). On 17 July, eruption columns with high ash content reached heights of 5 km above the summit (32,900 ft a.s.l.). On 18 July, moderate explosions produced steam columns that reached maximum heights of 3 km above the crater (26,300 ft a.s.l.). A child died after ash inhalation complicated a heart illness.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Reuters, Prensa Latina


5 July-11 July 2006

During 5-11 July, seismic activity indicating explosions increased at Tungurahua. Incandescent blocks were ejected from the crater during 5 to 8 July, when blocks rolled approximately 1 km down the NW flank. Ash-and-steam plumes with moderate to no ash content were observed to reach maximum heights of 2.5 km above the summit (24,700 ft a.s.l.) and drifted generally to the W and NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 June-4 July 2006

During 28 June- 4 July, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash that reached heights of 1.5 km above the summit (21,400 ft a.s.l.). Light ashfall was reported in nearby localities during 29 June-2 July. On 29 June, reports of ground movement coincided with an explosive eruption that generated blocks of incandescent material observed to roll 100 m down the W flank. Night-time incandescence was observed intermittently during the reporting period.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 June-27 June 2006

During 21-27 June, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash that reached heights of 1 km above the crater (19,800 ft a.s.l.). Light ashfall was reported in nearby localities on 21, 24-25 June. Night-time incandescence was observed from 24 to 26 June.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


14 June-20 June 2006

Explosions and seismic activity at Tungurahua were at moderate levels during 14-20 June. Steam columns with low-to-moderate ash content reached heights of 1.5 km above the summit (21,400 ft a.s.l.) on 14-15 and 17 June and drifted W. On 16 June, ash fell in the towns of Pillate and Bilbao.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 June-13 June 2006

During 7-13 June, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash. On 9 and 11 June, light ashfall was reported in nearby areas. According to the Washington VAAC, night-time incandescence was observed on satellite imagery through the reporting period.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Washington Volcanic Ash Advisory Center (VAAC)


31 May-6 June 2006

During 3-5 June, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash. On 5 June, light ashfall was reported in areas on the SW flank. Night-time incandescence was observed on 3 and 5 June.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 May-30 May 2006

During 24-30 May, visual observations of Tungurahua were limited due to heavy cloud cover. On 23 May, an ash plume reported by a pilot reached an altitude of 6.4 km (21,000 ft) a.s.l. A faint plume was visible on satellite imagery that drifted WSW. Slight ashfall was reported to the SW in Puela on 24 May, and the observatory reported a decrease in gas and ash emissions. On 25 May a significant meteorological advisory (SIGMET) indicated an ash plume to an altitude of 5 km (16,500 ft) a.s.l. On 27 and 30 May, the VAAC reported that the Instituto Geofísico observed ash plumes at altitudes of 7.9 km (26,000 ft) a.s.l. and 5 km (16,500 ft) a.s.l., respectively.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Reuters


17 May-23 May 2006

During 17-20 May, ash emissions from Tungurahua increased. On 18 May, an ash plume reached a height of 5.2 km (17,000 ft) a.s.l. and extended NW, according to Washington VAAC reports. The Washington VAAC also noted that on 19 May, the Instituto Geofísico observed an ash plume that reached a height of 12 km (40,000 ft) a.s.l. On satellite imagery, ash plumes were visible on 20 and 23 May and extended SW. Hotspots were visible on satellite imagery 19-20 and 23 May. The ash plume and incandescence on 23 May were also observed by Instituto Geofísico staff.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Reuters


10 May-16 May 2006

During 15-16 May, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash. A news article reported that on 15 May blasts could be heard within 20 km of the volcano, and a moderate-to-large explosion was heard in nearby communities. On 16 May, a plume reached a height of ~2 km above the crater (or 23,000 ft a.s.l.) and drifted W.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


3 May-9 May 2006

During 4-8 May, small-to-moderate explosions at Tungurahua produced plumes composed of gas, steam, and small amounts of ash. Seismicity was at relatively high levels and was dominated by signals from long-period earthquakes and explosions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 April-2 May 2006

During 28 April-1 May, small-to-moderate explosions at Tungurahua produced gas, steam, and small amounts of ash. Seismicity was at relatively high levels. A plume rose to a maximum height of ~2 km above the volcano (or 23,050 ft a.s.l.) on 28 April.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 April-25 April 2006

During 19-23 April, small-to-moderate explosions at Tungurahua produced gas, steam, and small amounts of ash. Seismicity was at relatively high levels. Plumes rose to ~3 km above the volcano (or 26,300 ft a.s.l.) on 19 April.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 April-18 April 2006

During 11-17 April, small-to-moderate explosions at Tungurahua produced gas, steam, and small amounts of ash. Seismicity was at relatively high levels. Plumes rose to ~2 km above the volcano (or 23,000 ft a.s.l.) on 13 April. A small amount of ash fell in the Pondoa sector N of the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 April-11 April 2006

During 4-10 April, small-to-moderate explosions at Tungurahua consisted of gas, steam, and small amounts of ash. Plumes rose to ~3 km above the volcano (or 26,300 ft a.s.l.) on 9 April. Ash fell in the Baños, Guadalupe, Choglontus, Bilbao, and Manzano sectors. Around 1500 on the 9th, several lahars traveled down gorges mainly on the W side of the volcano, disrupting traffic along the Baños-Penipe highway.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


29 March-4 April 2006

During 29 March to 2 April, small-to-moderate explosions at Tungurahua consisted of gas, steam, and small amounts of ash. During the report period, ash fell in the Bilbao, Choglontos, Puela, and Manzano sectors, and incandescent blocks rolled down the volcano's NW flank.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


22 March-28 March 2006

During 22-27 March, small-to-moderate explosions occurred at Tungurahua that consisted of gas, steam, and small amounts of ash. Plumes rose as high as ~1 km above the volcano (19,750 ft a.s.l.) on several days. An explosion on 26 March was accompanied by incandescent blocks that rolled down the volcano's NW flank.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


15 March-21 March 2006

During 16-20 March, small-to-moderate explosions occurred at Tungurahua that consisted of gas, steam, and small amounts of ash. Plumes rose to a height of ~3 km above the volcano (or 26,300 ft a.s.l.).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 March-14 March 2006

During 8-10 March, several explosions with low ash content produced plumes that reached no higher than 2 km above the volcano (or 23,050 ft a.s.l.). Light drizzle produced muddy water in the gorges on the volcano's W flank, so the Baños-Penipe highway was closed for several hours. On 9 March, ash fell in the zone of Juive on the volcano's NW flank. On 10 March, ash fell in the towns of Pillate, Pondoa, Runtún, and Cusúa (on the W and NW flanks of the volcano).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 March-7 March 2006

Activity at Tungurahua during 28 February to 6 March consisted of low-level seismicity and emissions of steam and gas, with low ash content. An explosion on the 28th produced a plume composed of steam, gas, and some ash that reached ~3 km above the volcano (or 26,300 ft a.s.l.).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 February-28 February 2006

Activity at Tungurahua during 26-27 February consisted of emissions of steam and gas, with low ash content. An explosion on the 26th at 1600 produced a NW-drifting gas-and-ash plume to ~3 km above the volcano (or ~26,300 ft a.s.l.). After noon on the 27th, an emission of steam and gas with low ash content rose to ~1 km above the volcano (or 19,750 ft a.s.l.) and drifted NW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 February-21 February 2006

Activity began to increase slightly at Tungurahua around 15 February. Several moderate explosions occurred during 15-19 February, with ash plumes rising as high as 3 km above the volcano (or 26,300 ft a.s.l.) on 15 February. Small amounts of ashfall were reported NW of the volcano in Cotaló, Cusúa, Pondoa, Bilbao, and at the Tungurahua Observatory (OVT) on the 18th. Rainfall generated a small mudflow SW of the volcano in the Quebrada Rea sector of Puela on 19 February.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 February-14 February 2006

During 6-14 February, several moderate-sized emissions of gas and ash occurred at Tungurahua, with plumes rising to ~500 m above the volcano (or 18,100 ft a.s.l.). On the 6th, the number of long-period earthquakes increased. An explosion around midnight on 12 February expelled incandescent volcanic material that traveled down the N flank of the volcano. A small amount of ash fell in the town of Puela, SW of the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 February-7 February 2006

During 1-7 February, emissions of gas and ash occurred at Tungurahua. On 5 February at 0600, a moderate explosion occurred. A steam plume, with a small amount of ash, rose to ~1 km above the volcano (or 19,750 a.s.l.) and drifted SW. Light rainfall on the 7th generated a lahar in La Pampa area NW of the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 January-31 January 2006

During 25-31 January, volcanic activity at Tungurahua remained at low levels with small emissions of steam and gas, with low ash content. On the 25th light rain caused lahars to flow in the NW sector of the volcano. The lahars descended a gorge from the village of Juive, causing the closure of the Banos-Penipe highway. Around the 28th, ash fell in the village of Puela. On the 31st, a steam-and-ash plume rose ~1 km above the volcano (or 19,750 ft a.s.l.) and drifted W. A small lahar traveled in the sector of Pampas, closing a road in the area for 2 hours.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 January-24 January 2006

At the beginning of January there was an increase in volcanic activity, and explosions generated moderate amounts of ash; seismicity remained low. Though clouds obscured the volcano during much of 18-24 January 2006, steam clouds with minor ash content were seen on 20 and 22 January. Muddy, sediment-laden water discharge down the W flank on 23-24 January blocked a highway. At the beginning of January there was an increase in volcanic activity, and explosions generated moderate amounts of ash; seismicity remained low. Though clouds obscured the volcano during much of 18-24 January 2006, steam clouds with minor ash content were seen on 20 and 22 January. Muddy, sediment-laden water discharge down the W flank on 23-24 January blocked a highway.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 January-17 January 2006

Small-to-moderate explosions at Tungurahua were preceded by long-period earthquakes during 11-16 January. An explosion on 11 January produced a plume with a moderate amount of ash. The plume drifted E.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


4 January-10 January 2006

IG reported that during 4-7 January, there was a slight change in the activity at Tungurahua in comparison to previous weeks, with more small-to-moderate explosions occurring. The explosions produced plumes of gas and small amounts of ash that rose to ~1 km above the volcano (or 19,750 ft a.s.l.). Seismicity remained at low levels.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


28 December-3 January 2006

During 28 December to 2 January, volcanic activity at Tungurahua remained at low levels with small emissions of steam and gas, with low ash content. Plumes rose to a maximum height of 6.1 km (20,000 ft) a.s.l. on 29 December and 2 January.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


14 December-20 December 2005

On 13 December, lahars were generated at Tungurahua that traveled down the Juive (NNW) and Achupashal (NW) gorges. On 14 December a steam-and-ash cloud rose ~1 km above the volcano (or 19,750 ft a.s.l.). On 17 December, lahars were generated in the NW and W zone of the volcano. There were reports of lahars to the W in the Chontapamba sector that blocked the Baños - Penipe highway, in the Salado sector where the volume of water in the Vazcún River increased by 70 percent, and in the Pampas sector.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 November-29 November 2005

During 23-28 November, volcanic activity at Tungurahua remained at low levels with small emissions of steam and gas, with low ash content. Plumes rose to a maximum height of ~6.7 km (22,000 ft) a.s.l. on 23 November.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 November-22 November 2005

During 15-21 November, volcanic activity at Tungurahua remained at low levels with small emissions of steam and gas, with low ash content. Plumes rose to a maximum height of ~9.1 km (30,000 ft) a.s.l. on 15 November.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 November-15 November 2005

During 9-14 November, volcanic activity at Tungurahua remained at low levels as it has since mid-February 2005. There were small emissions of steam and gas with low ash content. During the evening of 13 November lahars traveled down the volcano's W flank, leading to the temporary closure of the Baños -Riobamba highway. On 14 November, a steam emission with little ash reached a height of ~500 m above the volcano's summit (or 18,100 ft a.s.l.).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 November-8 November 2005

During 2-6 November, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and low ash content. Rain mixed with ash deposits and produced lahars on 3 November in the N and W sectors of the volcano, leading to the temporary closure of the Baños-Riobamba highway, and a highway in Pampas.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


26 October-1 November 2005

During 26-31 October, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and low ash content. On 30 October, clouds with low ash content reached heights of 500-1,000 m above the volcano's crater (or 18,100-19,750 ft a.s.l.) and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


19 October-25 October 2005

During 19-25 October, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and low ash content. Heavy rain caused lahars to travel down some of the gorges on the volcano's flanks. During the morning of 25 October a steam cloud was seen rising 200 m (660 ft) above the crater and drifting E.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 September-4 October 2005

During 28 September to 3 October, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and variable ash content. A pilot reported an ash plume on 29 September at a height of ~6.1 km (20,000 ft) a.s.l.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


21 September-27 September 2005

During 21-26 September, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and variable ash content. A small amount of ash fell in the towns of Cusúa (NW) and Bilbao (8 km W of the volcano) during the morning of 21 September. Fumaroles on the outer edge of the crater were visible from Runtún after not being seen for 6 months. Steam-and-gas plumes rose ~ 1 km above the volcano (or 19,800 ft a.s.l.) and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


14 September-20 September 2005

During 14-19 September, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and variable ash content. On 14 September, a steam column with little ash reached a height of ~300 m above the crater (or 17,500 ft a.s.l.) and drifted W. Small amounts of ash fell in Puela, ~8 km SW of the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


7 September-13 September 2005

During 7-12 September, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and variable ash content. The highest rising emission reached ~ 1 km above the volcano (or 19,750 ft a.s.l.) on 11 September. A lahar on 10 September affected an area near the new Baños-Penipe highway.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


31 August-6 September 2005

During 1-5 September, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and variable ash content. On 1 September, ash fell in the Puela sector, ~ 8 km SW of the summit.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 August-30 August 2005

During 24-29 August, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and variable ash content. On 25 August, ash fell in the towns of Bilbao (8 km W of the volcano) and Cusúa (NW of the volcano).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 August-23 August 2005

During 17-22 August, volcanic activity at Tungurahua remained at low levels with small emissions of steam, gas, and variable ash content. On 21 and 22 August, ash fell in the town of Bilbao 8 km W of the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 July-26 July 2005

During 20-26 July, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy plumes were emitted that were composed of gas, steam, and occasionally small amounts of ash.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 July-19 July 2005

During 13-18 July, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy plumes were emitted that were composed of gas, steam, and occasionally small amounts of ash. The highest rising plume was emitted on 14 July and rose ~800 m above the volcano (~19,100 ft a.s.l.) and drifted W.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 July-12 July 2005

During 6-11 July, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy plumes were emitted that were composed of gas, steam, and occasionally small amounts of ash. Seismicity remained at low levels.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 June-5 July 2005

During 1-5 July, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy plumes were emitted that were composed of gas, steam, and occasionally small amounts of ash. The plumes rose to a maximum height of ~5.8 km (19,000 ft) a.s.l. on 4 July.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 June-28 June 2005

On 24 June a narrow plume was identified in multispectral satellite imagery about an hour after an ash eruption was observed by the Instituto Geofísico. The ash plume was at an altitude of ~5.5 km (18,000 ft a.s.l.) and extended 35-45 km (20-25 nautical miles) W from the summit.

Sources: Washington Volcanic Ash Advisory Center (VAAC), Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 June-14 June 2005

During 7-13 June, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy plumes were emitted that were composed of gas, steam, and occasionally small amounts of ash. On 7 June fine ash fell in the Puela sector, ~8 km SW of the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


18 May-24 May 2005

Volcanic and seismic activity remained at relatively low levels at Tungurahua during 18-23 May, with mainly emissions of steam and gas. On 19 May around 1200 an emission produced an ash-and-steam plume to a height of ~500 m (18,100 ft a.s.l.) that drifted N.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 April-3 May 2005

During 27 April to 3 May, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 April-26 April 2005

During 20-25 April, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted. On 20 and 21 April rain generated lahars that traveled down the volcano's W flank near the settlement of Bilbao (8 km W).

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 April-19 April 2005

During 14-17 April, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted. On 18 April at 2057 a moderate explosion occurred that sent incandescent volcanic blocks rolling down the volcano's flanks. Ash fell S of the city of Ambato.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 April-12 April 2005

During 7-11 April, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 March-5 April 2005

During 30 March to 4 April, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted, and long-period earthquakes were recorded.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 March-29 March 2005

During 23-28 March, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted, and long-period earthquakes were recorded.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 March-22 March 2005

During 16-21 March, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted, and long-period earthquakes and episodes of tremor were recorded.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


9 March-15 March 2005

During 9-14 March, volcanic and seismic activity were at relatively low levels at Tungurahua. Low-energy gas-and-steam plumes were emitted, and long-period earthquakes and episodes of tremor were recorded.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 March-8 March 2005

Volcanic and seismic activity were at relatively low levels at Tungurahua during 3-7 March. Low-energy gas, steam, and ash plumes were emitted. In addition, long-period earthquakes and episodes of tremor were recorded.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


23 February-1 March 2005

Volcanic and seismic activity were at relatively low levels at Tungurahua during 23-28 February. Low-energy gas, steam, and ash plumes were emitted. In addition, long-period earthquakes and episodes of tremor were recorded. During the report period ashfall was reported in towns near the volcano, including Puela (SW of the volcano), San Juan de Pillate, Cusua, and Quero. On 23 February the daily sulfur-dioxide flux was 1,200 tons. On 27 and 28 February, rains generated lahars in the W zone of the volcano into the gorges of Cusua and Bilbao.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 February-22 February 2005

Volcanic and seismic activity were at low levels at Tungurahua during 16-22 February. Low-energy gas, steam, and ash plumes were emitted. In addition, long-period earthquakes and episodes of tremor were recorded.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


9 February-15 February 2005

Volcanic and seismic activity were at low levels at Tungurahua during 9-14 February. Low-energy gas-and-steam plumes were emitted and long-period earthquakes were recorded.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


2 February-8 February 2005

Volcanic and seismic activity were at low levels at Tungurahua during 2-7 February. Low-energy gas-and-steam plumes were emitted and long-period earthquakes were recorded.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 January-1 February 2005

Ash emission from Tungurahua on the evening of 25 January deposited a small amount of ash in the sector of Puala. On 26 July ash was deposited on the volcano's N and W flanks. The character of the eruption changed on 30 January to low-energy emissions of predominately steam. This type of activity continued through 31 January.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 January-25 January 2005

During 19-24 January, there were several emissions from Tungurahua of steam, gas, and ash. The plumes that were produced rose to a maximum height of ~1 km above the volcano and drifted in multiple directions. During the report period, small amounts of ash fell in the sectors of Agoyán, San Francisco, Runtón, Pondoa, and Baños. Seismicity was at relatively low levels.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 January-18 January 2005

Seismicity remained low at Tungurahua during 12-18 January with few to several long period events each day. On 14 January, a white column of steam-and-gas was observed that reached a height of 500 m above the crater and extended to the NW. On 16 January, a steam-and-gas plume reached a height of 200-300 m above the crater and extended SE. Incandescence was observed emanating from the crater during 12-13 January.

On 18 January, the Washington VAAC reported an ash plume that reached a height of ~5.5 km a.s.l. and extended to the E of Tungurahua's summit for ~15 km.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 January-11 January 2005

Increased seismicity and volcanic tremor registered at Tungurahua during 5-6 January. There were eleven signals suggesting volcanic emissions and one small explosion. Seismicity then returned to a low level. On 11 January, steam plumes rose ~300 m above the volcano and extended WNW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 December-4 January 2005

On 2 January, Tungurahua remained at a low level of activity with weak gas-and-steam emissions containing only a moderate amount of ash. Two small explosions were recorded.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 December-28 December 2004

During 22-27 December, activity at Tungurahua consisted of small-to-moderate explosions, several long-period earthquakes, and episodes of tremor. Emissions of steam, gas, and small amounts of ash rose to a maximum height of 1.5 km above the volcano on 22 December.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 December-21 December 2004

During 15-20 December, activity at Tungurahua consisted of small-to-moderate explosions, several long-period earthquakes, and episodes of tremor. Emissions of steam, gas, and small amounts of ash rose to a maximum height of 2 km above the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 December-14 December 2004

During 12-14 December, activity at Tungurahua consisted of small-to-moderate explosions and several long-period earthquakes. Emissions of steam, gas, and small amounts of ash rose to a maximum height of 2 km above the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


1 December-7 December 2004

During 1-6 December, activity at Tungurahua consisted of small-to-moderate explosions and several long-period earthquakes. Emissions of steam, gas, and small amounts of ash rose to a maximum height of ~2 km above the volcano. On the afternoon of 1 December, a small amount of ash fell N of the volcano in the sector of Juive.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


24 November-30 November 2004

During 26-29 November, activity at Tungurahua consisted of small-to-moderate explosions and several long-period earthquakes. Emissions mainly consisted of steam, gas, and small amounts of ash that rose to ~2 km above the volcano. During the morning of 28 November a small amount of ash fell on the village of Puela, ~8 km SW of the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 November-23 November 2004

Volcanic and seismic activity at Tungurahua during the report period were at relatively low levels, characterized by several long-period earthquakes and small to moderate explosions. Emissions mainly consisted of steam, gas, and small amounts of ash. During 17-18 November, explosions generated steam columns that rose 300-500 m above the summit of the volcano and drifted SSW.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 November-16 November 2004

Volcanic and seismic activity at Tungurahua during the report period were at relatively low levels, characterized by several long-period earthquakes and small to moderate explosions. Emissions mainly consisted of steam, gas, and small amounts of ash. On 15 November, incandescence was observed in the crater of the volcano and explosions generated steam columns with moderate ash content that rose ~2 km above the crater and drifted S.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 November-9 November 2004

Volcanic and seismic activity at Tungurahua during 4-7 November were at relatively low levels, characterized by a few long-period earthquakes and small explosions. Emissions mainly consisted of steam, gas, and small amounts of ash.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


27 October-2 November 2004

During 27 October to 1 November, volcanic activity at Tungurahua was at moderate levels, with several explosions producing plumes of gas, steam, and ash. On 27 October an explosion produced an ash column to a height of ~3.5 km above the volcano. During the evening ash fell in the towns of Baños, Runtún, and El Salado. Explosions on 31 October also deposited small amounts of ash in Bilbao and Motilone.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


20 October-26 October 2004

Volcanic and seismic activity at Tungurahua during 21-26 October were at relatively low levels, characterized by a few long-period earthquakes, tremor, and small explosions. Emissions mainly consisted of steam, gas, and ash.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


13 October-19 October 2004

Volcanic and seismic activity at Tungurahua during 13-18 October were at relatively low levels, characterized by a few long-period earthquakes, tremor, and small explosions. Emissions mainly consisted of steam and gas.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


6 October-12 October 2004

Volcanic and seismic activity at Tungurahua during 11-12 October were at relatively low levels, characterized by a few long-period earthquakes and small explosions. Emissions mainly consisted of steam and gas, with small amounts of ash.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 September-5 October 2004

During 29 September to 5 October seismic and volcanic activity at Tungurahua were at relatively low levels, with the occurrence of occasional small explosions of gas, steam, and ash and some long-period earthquakes.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 September-28 September 2004

During 21-27 September, relatively low-level activity continued at Tungurahua. There were emissions of gas, steam, and ash. In addition, sporadic explosions produced plumes to a maximum height of 3 km above the volcano. On the evening of 21 September, Strombolian activity was seen, with volcanic blocks thrown as high as 200 m above the volcano.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 September-21 September 2004

Throughout this period, Tungurahua exhibited weak gas emissions and crater glow. Tremor and long-period events were associated with steam emissions. The IG daily report on 20 September noted that some explosions generated plumes with ash, casuing ashfall in Bilbao and Pondoa. Columns with moderate ash content reached 1 km above the vent.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 September-14 September 2004

During 9-13 September volcanic and seismic activity were at low levels at Tungurahua, with the occurrence of weak steam-and-ash emissions and sporadic long-period earthquakes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


1 September-7 September 2004

During 2-6 September volcanic and seismic activity were at low levels at Tungurahua, with the occurrence of weak steam-and-ash emissions and sporadic long-period earthquakes. Incandescence was visible in the crater on the evening of 2 September.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


25 August-31 August 2004

During 25-31 August, volcanic and seismic activity were at low-to-moderate levels at Tungurahua. Emissions of gas, steam, and ash rose to low levels above the volcano and were accompanied by tremor. In addition, several long-period earthquakes occurred during the report period.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


18 August-24 August 2004

Volcanic and seismic activity at Tungurahua remained at low levels during 18-23 August. Emissions of gas, steam, and ash rose to low levels above the volcano and a small number of long-period earthquakes occurred.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


11 August-17 August 2004

Volcanic and seismic activity at Tungurahua remained at low levels during 11-17 August. Emissions of gas, steam, and ash rose to ~1.5 km above the volcano and a small number of long-period earthquakes occurred.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


4 August-10 August 2004

The number of seismic signals at Tungurahua related to emissions and volcanic events were low from 24 July to 9 August. During 4-9 August, occasional explosion earthquakes were recorded.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 July-3 August 2004

Volcanic and seismic activity remained at relatively low levels at Tungurahua during 28 July to 2 August, with emissions of gas, steam, and small amounts of ash rising to ~500 m above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


21 July-27 July 2004

During 25-26 July, volcanic and seismic activity were at low levels at Tungurahua. A few sporadic long-period earthquakes were related to small emissions from the volcano. Inclement weather prohibited observations of the emissions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


14 July-20 July 2004

Volcanic and seismic activity at Tungurahua remained at moderate levels. Tremor was associated with emissions of steam, gas, and ash.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 July-13 July 2004

The volcanic and seismic activity at Tungurahua continued at moderate levels, including small explosions that resulted in light ash fall on many communities and about 100 long-period earthquakes per day. Incandescence in the crater was observed at night on several occasions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


30 June-6 July 2004

During 29 June to 5 July the level of volcanic and seismic activity diminished at Tungurahua in comparison to the previous week, with sporadic moderate explosions of ash and gas. The highest rising plume reached ~1.5 km above the volcano. During the report period, seismicity was at relatively low levels.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


23 June-29 June 2004

At Tungurahua during 23-28 June, there were several emissions of steam, gas, and moderate amounts of ash. About 5-10 small-to-moderate explosions occurred daily. Plumes from eruptions rose to ~1.5 km above the crater. Seismicity was characterized by long-period earthquakes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


16 June-22 June 2004

During 16-21 June, there was a slight increase in volcanic activity at Tungurahua in comparison to the previous weeks. There were several emissions of steam, gas, and moderate amounts of ash, and 5-10 explosions occurred daily. Seismicity was characterized by long-period earthquakes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


9 June-15 June 2004

Several explosions occurred at Tungurahua on 10 June, with the largest rising ~3 km above the volcano and drifting W. A small amount of ash fell in the Pillate area and a lahar destroyed a bridge in the Bibao zone.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


2 June-8 June 2004

During 2-8 June, activity remained at a moderate level at Tungurahu with several weak to moderate explosions recorded per day. Sporadically observed gas-and-ash and gas-and-steam plumes rose up to 1 km above the summit. A strong explosion on 5 June produced a gas-and-ash plume that rose 2 km above the summit. All plumes drifted W. Seismicity remained at moderate levels for the reporting week. On 3 June, possible lahars were noted on the N and NW flanks.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 May-1 June 2004

During 26-31 May, small-to-moderate emissions of steam, gas, and ash occurred at Tungurahua and seismicity was at moderate levels.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 May-25 May 2004

During 19-24 May, small-to-moderate emissions of gas, steam, and ash continued at Tungurahua. The highest rising plume reached ~2.5 km above the volcano on 23 May. On the morning of 19 May a mudflow occurred in the Pampas sector, but it did not affect the highway. Strombolian activity was visible in the crater on the evening of 23 May.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 May-18 May 2004

During 12-17 May, moderate emissions of steam, gas, and ash continued at Tungurahua. On 12 May, an explosion produced an ash cloud to ~3 km above the volcano that drifted SW. On 13 May seismicity increased moderately, related to the increased numbers of emissions. Incandescence was visible at the lava dome during some nights.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 May-11 May 2004

During 5-11 May, emissions of gas and ash continued at Tungurahua. Based on information from IG, the Washington VAAC reported that ash rose to ~7 km a.s.l. on 10 May.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


28 April-4 May 2004

During 27 April to 4 May, emissions of gas and ash continued at Tungurahua. Volcano-tectonic earthquakes on 27 and 28 April preceded a slight increase in the number of sudden explosions at Tungurahua on 30 April. According to a news article, on 1 and 2 May ash fell in the towns of Cotaló and San Juan (W of the volcano). The level of seismicity at Tungurahua decreased on 4 May.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), El Universo


21 April-27 April 2004

Volcanic activity at Tungurahua during 22-26 April was at moderate levels. On 21 April, a column of steam, gas, and ash rose to a height of ~1 km above the volcano and drifted NW. Ash fell in Bilbao, Cusúa, San Juan, Cotaló, Pillate, and Juive sectors. A plume reached ~0.5 km on 22 April and deposited ash in the towns of Ambato (to the NW) and Baños (to the N). During the evening of 24 April, incandescence was visible in the crater and incandescent blocks rolled a few meters down the volcano's NW flank.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), El Universo


14 April-20 April 2004

During 13-18 April, activity at Tungurahua remained at low levels with few explosions reported. Seismicity was restricted to less than ten long-period earthquakes per day, with occasional episodes of tremor related to gas-and-steam emissions. Heavy rain during the afternoon and night of 13 April triggered a lahar that cut the La Pampa section of the Baños-Pelileo road.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 April-13 April 2004

During 7-11 April volcanic activity at Tungurahua was at low levels, with emissions of steam, gas, and very little ash. On the evenings of 10 and 11 April, incandescence was visible in the crater. Sulfur-dioxide flux measurements taken on 11 April were the highest measured for several weeks (1,600-1,700 tons per day).

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


31 March-6 April 2004

During 30 March to 3 April, volcanic activity at Tungurahua was at relatively low levels, but emissions of steam and ash occurred and incandescence was visible in the crater. On 4 April at 1902 an explosion produced a plume containing a moderate amount of ash that rose to 800 m above the crater.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


24 March-30 March 2004

Tungurahua remained at a low level of activity with constant degassing only interrupted by sporadic small explosions. During the night of 28-29 March incandescent material was observed avalanching on the upper slopes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


17 March-23 March 2004

During 16-23 March, degassing continued at Tungurahua with occasional explosions of steam, gas, and ash. In the afternoon of 15 March a lahar traveled in the Pampas sector.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


10 March-16 March 2004

During 11-15 March, degassing continued at Tungurahua with occasional explosions of steam, gas, and ash. On 11 March a lahar traveled in the Pampas sector.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


3 March-9 March 2004

During 4-8 March, degassing continued at Tungurahua with occasional explosions of steam, gas, and ash. According to a news article, on 2 March a lahar traveled through the sector of Pampas, but did not damage the Baños-Pelileo road.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), El Universo


25 February-2 March 2004

During 25 February to 1 March, degassing continued at Tungurahua with occasional explosions of steam, gas, and ash, producing plumes to ~500 m above the volcano. On 25 February a small amount of ash fell in the sector of Chontapamba. According to the Washington VAAC, ash plumes were sometimes visible on satellite imagery during the report period.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


18 February-24 February 2004

During 19-23 February, emissions of steam, gas, and ash continued at Tungurahua. On the afternoon of 19 February ash fell in the towns of Puela (~8 km SW of the volcano) and Pillate (~8 km W of the volcano). An explosion on 22 February at 2355 produced an avalanche of incandescent volcanic blocks that traveled ~1 km from the summit.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


11 February-17 February 2004

During 11-16 February, small-to-moderate explosions at Tungurahua produced steam, gas, and ash plumes to ~1 km above the volcano. On 11 February an avalanche of incandescent volcanic blocks traveled ~1 km down the volcano's flank.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


4 February-10 February 2004

On 5 February there was a slight increase in seismic activity at Tungurahua; steam emissions rose to low levels, and small lahars traveled down the volcano's W flank via the Achupashal and Chontapamba gorges. On 9 February emissions of steam, gas, and moderate amounts of ash occurred, and ash was deposited to the W in the sectors of Pillate and San Juan.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


28 January-3 February 2004

During 28 January to 2 February, Tungurahua continued to emit gas, steam, and ash. Emissions rose to ~2 km above the crater, with variable amounts of ash in the resultant plumes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


21 January-27 January 2004

During 21-26 January, Tungurahua continued to emit gas, steam, and ash. Emissions rose to ~1 km above the crater, with variable amounts of ash in the resultant plumes. On 22 January at 0626 an explosion sent a plume to ~2 km above the volcano. On the evening of 24 January ash fell in the areas of Puela and Penipe (~ 8 km SW of the volcano), and ash fell during 24-25 January in the city of Riobamba (~ 30 km SW of the volcano). During the report period, low-level seismicity occurred.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


14 January-20 January 2004

During 14-19 January, Tungurahua continued to emit gas, steam, and ash. Emissions rose to ~1 km above the crater and drifted predominately N and NE, with variable amounts of ash in the resultant plumes. In addition, low-level seismicity occurred.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 January-13 January 2004

Volcanic activity at Tungurahua during 7-13 January continued with emissions of gas, steam, and ash and low-to-moderate seismicity. Emissions reached ~1 km above the volcano and traveled W and SW on 8 January. Emissions on 12 January deposited ash in the sectors of Bilbao, Cusúa, Pillate, Ulba, Pondoa, Banos, Juive, Ambato, and Patate.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


31 December-6 January 2004

During 31 December to 5 January, emissions of gas, steam, and ash, and low-level seismicity continued at Tungurahua. Plumes rose to a maximum height of 3 km above the crater on 31 December. An emission on 4 January produced small amounts of ash that fell in the sector of Puela, ~8 km SW of the summit. During the report week, plumes were visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


24 December-30 December 2003

During 24-30 December, there were emissions of gas, steam, and ash, and low levels of seismicity at Tungurahua. On 28 December emissions sent plumes ~1.5 km above the volcano's summit that drifted E and NE. Ash fell in the sector of Runtún NNE of the volcano and in the city of Baños on the volcano's N flank. On 30 December aircraft personnel reported an ash cloud ~800 m above the volcano. According to the Washington VAAC, during the report period ash was visible on satellite imagery to a maximum height of ~3 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


17 December-23 December 2003

Volcanic activity continued at relatively high levels at Tungurahua during 17-22 December, with the occurrence of several moderate explosions. During the afternoon of 18 December a signal from a lahar in the sector of Cusúa NW of the volcano was recorded. According to the Washington VAAC, plumes from Tungurahua were visible on satellite imagery at a maximum height of ~7.5 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


10 December-16 December 2003

During 11-16 December, volcanic activity remained relatively high at Tungurahua with several explosions producing ash-and-gas plumes to a maximum height of 4 km. There were also many long-period earthquakes that were associated with near-constant gas-and-ash emissions. Explosions on 11 December deposited ash in the towns of Quero, Santa Fe de Galán, and lesser amounts in Bilbao. According to the Washington VAAC, ash-and-gas plumes were visible on satellite imagery several times during the report week.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


3 December-9 December 2003

During 3-9 December, frequent Strombolian eruptions occurred at Tungurahua. Ash plumes were dispersed up to ~90 km to the NNE, WNW, ESE, S, NW, and W and reached a maximum height of ~9 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 November-2 December 2003

During 22 November to 1 December, a large number of emissions of gas, steam, and ash occurred at Tungurahua, depositing ash to the SW, W, and NW. Plumes were visible on satellite imagery at a maximum height of ~7 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 November-25 November 2003

During 19-25 November, activity at Tungurahua remained high, with numerous moderate explosions producing plumes that were frequently visible on satellite imagery and rose up to 2 km above the crater. Ash was dispersed to the SSW and SW on 19 and 20 November and WNW and NW on 23 and 24 November, respectively. Throughout the week Strombolian activity was visible at night.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 November-18 November 2003

During 12-18 November, small-to-moderate eruptions of steam, gas, and some ash continued at Tungurahua. Plumes rose to ~2.5 km above the volcano, but there were no reports of ashfall in nearby towns. Strombolian activity was visible at the crater and avalanches of incandescent volcanic material rolled ~1 km down the volcano's flanks.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 November-11 November 2003

Tungurahua maintained a generally low level of activity, with occasional plumes (often ash-poor) rising to less than 1 km above the summit. In contrast, a few ash-bearing emissions occurred. For example, on 5, 6, and 7 November there were ash falls of low intensity in the volcano's eastern sector. On the 6th two larger than average explosions were recorded seismically, one associated with an ash column rising to 2 km a.s.l. On the latter day there was also a modest. During this week, tremor represented a key seismic signal, with relatively few earthquakes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


29 October-4 November 2003

During 29 October to 4 November, small-to-moderate eruptions of steam, gas, and ash continued at Tungurahua. An eruption on 2 November produced a plume that rose to ~3 km above the volcano and drifted W. Several plumes were visible on satellite imagery during the report week.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


22 October-28 October 2003

During 21-27 October, moderate-sized eruptions continued at Tungurahua. Ash plumes generally rose to ~2 km above the volcano. An emission on 26 October deposited ash in the town of Baños N of the volcano. On 27 October an eruption sent an ash plume to ~4 km above the volcano. Several ash plumes were visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), El Comercio


15 October-21 October 2003

During 15-19 October activity at Tungurahua remained high, with moderate-to-slight gas-and-ash emissions sending columns on average to 1.5 km above the crater. On the night of 18 October incandescent blocks were observed rolling down the W side of the crater. Incandescence and Strombolian activity were observed on the night of 19 October. Activity decreased slightly on 20 October with fewer explosions and no major gas-and-ash eruptions recorded. Ash plumes were frequently visible on satellite imagery during the week.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


8 October-14 October 2003

Moderate-to-large ash-and-gas emissions continued at Tungurahua during 8-14 October. Plumes reached an average height of 2 km above the volcano. On 9 October ashfall occurred in several sectors near the volcano, including Runtún, Juive,úa, Puela, and Baños. Strombolian activity was seen during the evening of 12 October, and gas-and-ash plumes drifted NNE. Ash fell in the town of Ambato.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


1 October-7 October 2003

Moderate-to-large ash emissions continued at Tungurahua during 1-7 October. On 1 October gas-and-ash emissions reached a height of ~4 km and drifted NE and NW, depositing ash in San Juan, Pillate, and Valle del Patate. Seismicity was dominated by long-period earthquakes and explosions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


24 September-30 September 2003

Moderate-to-large ash emissions continued at Tungurahua during 24-30 September. On 24 September ash emissions produced plumes that that drifted NW and deposited small amounts of ash in the towns of Quero, Puela, Juive, and Cusúa. Volcanic blocks emitted during the eruption rolled ~1 km down the volcano's NW flank.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


17 September-23 September 2003

Moderate-to-large ash emissions continued at Tungurahua during 19-26 September. A period of relatively high activity at Tungurahua during 9 September to at least 26 September consisted of nearly permanent tremor related to gas discharge, and strong ash emissions. On 22 September ash clouds reached a height of 3 km above the volcano and drifted W. Towns to the W of the volcano have been affected by the recent activity.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


10 September-16 September 2003

Moderate-sized ash emissions continued at Tungurahua during 10-15 September. On 15 September two emissions produced gas-and-ash plumes that reached a maximum height of 2 km above the volcano. Ash fell predominately W of the volcano, including in the towns of Juive, Pillate, and western Baños. Seismicity during the report period was at moderate levels.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


3 September-9 September 2003

Ash emissions continued at Tungurahua during 3-8 September. Ashfall occurred in the town of Pillate on 3 and 4 September and in the town of Mocha on 4 September. During the evening of 7 September incandescence was visible in the crater.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


27 August-2 September 2003

During 27 August to 1 September, volcanic block and ash emissions continued at Tungurahua. Ash plumes rose to a maximum height of ~4 km above the volcano. The plumes primarily drifted W and SW, depositing ash in several towns including Cotaló, Pillate, Cevallos, Guaranda, Guanujo, Riobamba, and Quero. An emission on 27 August at 1350 deposited ash in Ambato ~40 km NW of the volcano and caused flight restrictions to and from the airport there.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Agence France-Presse (AFP), El Comercio


20 August-26 August 2003

After 50 days of low activity, Tungurahua entered a new phase of activity on 20 August, characterized by a short sequence of long-period earthquakes followed by gas-and-ash emissions that reached a maximum height of 3 km above the volcano. A small amount of ash fell in the sector of Cusúa. During the evening incandescent volcanic blocks were hurled ~300 m above the volcano and traveled ~1 km down the volcano's flanks. On 21 August emissions of mostly steam and small amounts of ash rose ~1 km above the volcano and drifted W. Ash fell in the sectors of Riobamba, Ambato, and Santa Fé de Galán. On 23 August plumes rose to 0.5-2.5 km above the volcano, and ash fell in the town of Guaranda. On 24 August an explosion at 2133 ejected blocks that traveled ~1 km down the volcano's flanks. The explosion was heard in the town of Baños.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Agence France-Presse (AFP)


16 July-22 July 2003

Seismic and volcanic activity were at relatively low levels at Tungurahua during 16-22 July, with emissions of steam and gas forming low-level plumes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


9 July-15 July 2003

During 9-15 July, volcanic and seismic activity at Tungurahua remained at relatively low levels. IG reported that no immediate changes in activity are expected until there is a new injection of magma into the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


2 July-8 July 2003

Following an increase in the frequency of ash emissions at Tungurahua on 26 June, activity decreased on 2 July. On 1 and 2 July ash plumes rose to ~2 km above the volcano and ash fell in several towns near the volcano. In addition, Strombolian activity occurred. Ash from eruptions damaged crops and livestock near the volcano. After the 2nd, mainly gas and steam were emitted from the volcano. A state of emergency was declared on 3 July, and food rations were distributed to residents of the town of Chimborazo. The Alert Level at Tungurahua remained at Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone, as it has since 5 September 2000.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), El Comercio, Agence France-Presse (AFP)


25 June-1 July 2003

Several ash-cloud producing explosions occurred at Tungurahua during 25 June to 1 July. On 25 June ash fell in the sector of Pillate and in the town of Mocha. According to the Washington VAAC, ash was visible on satellite imagery during the report week, with the highest rising ash cloud reaching ~9.4 km a.s.l. on 27 June. Emissions on 29 June deposited ash in Pillate, and in the towns of Cotaló and Cevallos.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


18 June-24 June 2003

Explosions continued to occur at Tungurahua during 17-24 June. During the evening of 17 June, Strombolian activity was visible at the volcano's summit. An explosion on 18 June at 0222 deposited ash in the sectors of Cusúa, Juive, and Pillate. On 19 June IG observed ash to a height of ~3 km above the volcano. During much of the week gas emissions with small amounts of ash occurred.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


11 June-17 June 2003

Relatively high volcanic activity continued at Tungurahua during 10-17 June. Several explosions took place, with the highest rising ash plume reaching ~5 km above Tungurahua. Some explosions were heard in towns near the volcano and on 10 June vibrations from an explosion were felt in the town of Baños. Significant amounts of ash fell in several villages, including Quero and Pelileo. Strombolian activity during the evening of 15 June consisted of incandescent blocks that were hurled to ~150 m above the crater and rolled ~1 km down Tungurahua's N flank. Ash fell in the sector of Cusúa. During the report week, ash clouds were visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


4 June-10 June 2003

Volcanic activity increased at Tungurahua around 5 June. On the evening of 6 June Strombolian activity was observed, consisting of incandescent volcanic blocks being hurled ~500 m from the summit. Plumes composed mainly of steam rose to heights around 2 km above the volcano and drifted W. Ash fell in the towns of Pilate, San Juan, and Riobamba, depositing less than 1 mm of ash. According to the Washington VAAC, intense cloud cover prohibited identification of ash plumes on satellite imagery. On the 6th there were reports of ash interfering with main flight routes across Ecuador. IG reported emissions on the 9th reaching 3 km above the volcano and drifting W. On 9 June at 0815 an aircraft reported ash at a height of ~6 km above the volcano. The Alert Level at Tungurahua remained at Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone, as it has since 5 September 2000.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 May-13 May 2003

Based on information from IG, the Washington VAAC reported that a small explosion at Tungurahua on 6 May produced a cloud composed mainly of gas, with some ash. The cloud drifted W and seismic activity decreased after the explosion.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


30 April-6 May 2003

Although limited visibility often prevailed, Tungurahua's behavior alternated between days of tranquility and those with small to moderate explosions. Few earthquakes occurred. On 1 May an explosion sent ash to 2 km above the summit; incandescent material fell onto the flanks up to 800 m from the crater.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


16 April-22 April 2003

Although activity was generally low during the week of 16-22 April, more volcanic explosions continued at Tungurahua. Many of these events were small, and minor vapor columns were also noted. Cloud cover obscured the volcano on some days. A 16 April aviation report discussed an ash cloud seen by IG rising up to ~7 km a.s.l. (~2 km above the summit). On 17 April two ash columns rose 1.5 and 2 km above the summit and blew SW and W, respectively. Although the volcano generally appeared relatively placid, there remained concern about sudden increases in eruptive output and about mudflows.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


9 April-15 April 2003

Activity at Tungurahua during 9-14 April was relatively low, with sporadic explosions. The largest reported explosion occurred on 10 April and produced a plume with low ash content to ~2 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


2 April-8 April 2003

During 2-7 April, explosions occasionally occurred at Tungurahua. According to the Washington VAAC, a pilot reported seeing ash at a height of around 2.3 km over Tungurahua on 6 April at 1810. No ash was detected on satellite imagery. IG reported that three explosions occurred on 7 April, with the largest plume rising to ~3 km above the volcano. Very little ash was visible in the plume.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 March-25 March 2003

During 19-25 March, sporadic explosions occurred at Tungurahua. On the 19th an explosion that was accompanied by Strombolian activity sent incandescent material ~1 km down the volcano's flanks. IG stated that after 13 March intense tremor was not recorded and the intensity of explosions decreased.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 March-18 March 2003

During 11-18 March, several explosions occurred at Tungurahua. On the 11th three small-to-moderate explosions deposited ash in the town of Pillate. According to the Washington VAAC, a pilot reported ash to a height of ~8.2 km a.s.l. that day. On the 16th a fine layer of ash was deposited in the N-flank resort town of Baños. Explosions during the report period were accompained by Strombolian activity, gas-and-ash emissions, and loud roaring sounds. Seismicity was dominated by tremor and long-period earthquakes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 March-11 March 2003

On 5 March at 1539 lahars began to descend the gorges on Tungurahua's W flank, obstructing the route between the towns of Baños and Pelileo. Around 7 March volcanic and seismic activity intensified at Tungurahua and according to the Washington VAAC, IG reported that ash from an explosion rose to ~7 km a.s.l. and drifted SW. No ash was visible on satellite imagery. IG also reported that by 9 March several low-to-moderate explosions had occurred at Tungurahua, which were accompanied by Strombolian activity, gas-and-ash emissions, and loud roaring sounds. Seismicity was dominated by tremor and long-period earthquakes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 February-4 March 2003

Seismic and volcanic activity were at low levels at Tungurahua during 26 February to 4 March, with emissions of steam, gas, and ash forming low-level plumes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 February-25 February 2003

Seismic and volcanic activity remained at low-to-moderate levels at Tungurahua during 19-20 February, with emissions of steam, gas, and ash producing low-level plumes. A moderate explosion on 19 February at 0249 deposited a small amount of ash in the sector of Ulba. Seismicity increased slightly during the eruption, but returned to low levels afterwards.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 February-18 February 2003

Seismic and volcanic activity remained at low-to-moderate levels at Tungurahua during 7-14 February, with emissions of steam, gas, and ash producing low-level plumes. Based on information from IG, the Washington VAAC reported that an emission occurred on 12 February at 1657 that rose to low levels and drifted W. No ash was visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 February-11 February 2003

Seismic and volcanic activity remained at relatively low levels at Tungurahua during 5-11 February, with emissions of steam, gas, and ash producing low-level plumes. Incandescence was visible in the crater during some evenings.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


29 January-4 February 2003

Seismic and volcanic activity remained at relatively low levels at Tungurahua during 29 January to 4 February, with emissions of steam, gas, and ash producing low-level plumes. Incandescence was visible in the crater during some evenings.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


22 January-28 January 2003

Seismic and volcanic activity remained at relatively low levels at Tungurahua during 22-27 January, with emissions of steam, gas, and ash producing low-level plumes. Incandescence was visible in the crater during some evenings.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


15 January-21 January 2003

Volcanic activity remained at relatively low levels at Tungurahua during 15-21 January, with emissions of steam, gas, and ash producing low-level plumes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


8 January-14 January 2003

Volcanic activity remained at relatively low levels at Tungurahua during 8-13 January. Incandescence was visible in the crater at night. Seismicity was characterized by sporadic long-period earthquakes and low-intensity emissions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


31 December-6 January 2003

Based on information from IG, the Washington VAAC reported that an explosion occurred at Tungurahua on 30 December at 1136. The resultant plume rose to ~9.5 km a.s.l. After the explosion until at least 5 January, incandescence in the crater became more intense, suggesting the presence of lava. The absence of Strombolian activity suggested that the magma was very degassed. As of 5 January, seismicity had been low for a week.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


18 December-24 December 2002

During 18-22 December, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to ~1 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


11 December-17 December 2002

During 11 December, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to ~1 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


4 December-10 December 2002

During 4-9 December, emissions of steam, gas, and ash continued at Tungurahua. The highest reported ash cloud was produced from an eruption on 4 December at 1215. It reached a height of 3.5 km above the volcano and drifted NW. Ashfall occurred in the settlements of Arrayan and Pilate. During 6-8 December, seismicity slightly increased from relatively low levels the rest of the week.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


27 November-3 December 2002

During 27 November to 1 December, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to ~1 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


20 November-26 November 2002

During 21-24 November, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to ~1 km above the volcano and incandescence was seen during some evenings. IG warned that lahars could be generated during heavy rain.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


13 November-19 November 2002

During 14-18 November, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to ~1 km above the volcano and incandescence was seen during several evenings. A moderate explosion occurred on the 14th at dawn that was heard in the town of Ambato.

Source: Washington Volcanic Ash Advisory Center (VAAC)


6 November-12 November 2002

During 6-12 November, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to a maximum height of ~7 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


30 October-5 November 2002

During 30 October to 5 November, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to a maximum height of ~5.8 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


23 October-29 October 2002

During 22-29 October, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to a maximum height of ~8 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


16 October-22 October 2002

During 16-22 October, emissions of steam, gas, and ash continued at Tungurahua. Plumes rose to a maximum height of ~8 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


9 October-15 October 2002

During 9-15 October, emissions of steam, gas, and ash continued at Tungurahua. Ash was seen rising to a maximum height of ~7.9 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


2 October-8 October 2002

A relatively large eruption at Tungurahua on 2 October at 0828 produced an ash cloud that rose to a maximum height of ~14.3 km a.s.l. By 1115 on the 2nd the high-level plume had detached from the volcano and there were two areas of ash visible in satellite imagery; one was at ~14.3 km a.s.l. and the other was at ~7.6 km a.s.l. By 1745 no ash was detected on satellite imagery, however, ash was reported SW of Tungurahua over the town of Riobamba at 1700. According to a news report, ashfall was reported in the region NW of the volcano around the towns of Ambato and Patate. IG reported that activity decreased on the morning of 3 October and visible satellite imagery did not reveal any ash in the vicinity of the volcano. The same day an ash cloud was produced to a height of ~7 km a.s.l. Orange Alert Level was in effect for the W side of the volcano, while a lower Yellow Alert Level was in effect in Baños at the northern base of the volcano.

Sources: Washington Volcanic Ash Advisory Center (VAAC), EFE News Service


25 September-1 October 2002

During 25 September-1 October, emissions of steam, gas, and ash continued at Tungurahua. Ash was seen rising to a maximum height of ~7 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


18 September-24 September 2002

During 7-13 September, emissions of steam, gas, and ash continued at Tungurahua. Ash was seen rising to a maximum height of ~7 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


11 September-17 September 2002

Activity at Tungurahua was very low during 9-12 September, with low gas emission (50 tons of SO2 on 12 September) and negligible seismic activity. On the 12th at 1300 a sudden ash emission occurred that marked the onset of a new eruptive phase. A dark ash column reached 1 km above the crater and drifted W. About 1.5 hours later the column turned white and roaring indicated that sustained Strombolian activity was taking place in the crater. Intense Strombolian activity was seen at night, with large amounts of ballistic material being thrown out of the crater and ash falling on the volcano's flanks. SO2 gas emission was relatively high (1,200 tons per day). By the next day activity began to decline; low-level Strombolian activity occurred and 700 tons of SO2 were emitted that day. On the 14th around 0100, long-lived and high-amplitude tremor suddenly started at the volcano. It was followed by an intense explosive phase that began near 1000 and continued through at least the 15th at 2200. During the eruptive episode, continuous gas-and-ash emissions and short-lived Vulcanian explosions occurred. Dark ash plumes occasionally rose 3-4 km above the crater and drifted SW. Large blocks were thrown as high as 700 m above the crater and landed as far as 2 km from the crater. Lava fountaining also occurred.

Sources: Institut de Recherche pour le Développement (IRD), Washington Volcanic Ash Advisory Center (VAAC)


28 August-3 September 2002

During 21-27 August, emissions of steam, gas, and ash continued at Tungurahua. Ash clouds reportedly rose to a maximum height of ~7.3 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


21 August-27 August 2002

During 21-27 August, emissions of steam, gas, and ash continued at Tungurahua. Ash clouds reportedly rose to a maximum height of ~7.3 km a.s.l.

Source: Washington Volcanic Ash Advisory Center (VAAC)


14 August-20 August 2002

During 14-20 August, emissions of steam, gas, and ash continued at Tungurahua. According to pilot reports, ash was seen rising to a maximum height of ~9.1 km a.s.l. Ash was not visible on satellite imagery.

Source: Washington Volcanic Ash Advisory Center (VAAC)


7 August-13 August 2002

During 7-13 August, emissions of steam, gas, and ash continued at Tungurahua. Ash was seen rising to a maximum height of ~6.7 km a.s.l., but it was not visible on satellite imagery.

Source: Washington Volcanic Ash Advisory Center (VAAC)


31 July-6 August 2002

Intermittent eruptive activity continued throughout the report period. Satellite observations were obscured the entire time, but visual reports by ground observers indicated frequent ash emissions. At least six pilot reports between 31 July and 6 August described ash plumes rising as high as 6 km a.s.l. and moving W or NW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


24 July-30 July 2002

Beginning on 22 July there was an increase in the number of explosive events at Tungurahua in comparison to the previous week. Explosions on 23 and 24 July reached an average height of ~2 km above the summit and drifted to the NW, W, and SW. Small amounts of ash fell in the sectors of Riobamba, SW of the volcano, and Baños, to the N. By 28 July, the level of volcanism had declined.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


17 July-23 July 2002

At Tungurahua during 16-22 July, there were several emissions of steam, gas, and ash, periods of continuous tremor, and incandescence was occasionally visible. Several explosions produced ash clouds to a maximum height of 3 km. On the evening of the 21st, in addition to a 1-km-high volcanic cloud, observers noted lava fountains and incandescent blocks rolling down the NW flank. On the morning of the 22nd, an eruption deposited relatively large amounts of ash NW of Tungurahua in the sectors of Ambato, Pillate, Pelileo, Cusua, and Chacauco.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


10 July-16 July 2002

Activity at Tungurahua during 9-14 July consisted of small-to-moderate emissions of steam, gas, and some ash, and periods of continuous tremor. During Strombolian activity on the 9th, incandescent volcanic bombs were hurled ~300 m into the air. A moderate explosion occurred on 12 July at 0517. Ash fell in the towns of Ambato, NW of Tungurahua, and Riobamba, to the SW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


3 July-9 July 2002

During 3-9 July, volcanic and seismic activity were relatively low at Tungurahua. Activity consisted of emissions of gas, steam, and ash. Ash clouds were reportedly seen up to ~7 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 June-2 July 2002

During 26 June-2 July, volcanism at Tungurahua consisted of small emissions of gas, steam, and ash. For several days, frequent explosions emitted rocks and incandescent material that traveled down the volcano's flanks. IG reported that an explosion on 1 July at 1123 produced an ash cloud that rose 1.5 km above the summit and drifted to the W.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 June-25 June 2002

During 19-23 June, volcanic and seismic activity were relatively low at Tungurahua. Activity consisted of emissions of gas, steam, and ash.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 June-18 June 2002

During 13-17 June, continuous degassing occurred at Tungurahua, accompanied by nearly continuous volcanic tremor, long-period earthquakes, and occasional small-to-moderate explosions sometimes preceded by volcano-tectonic events. On 13 June incandescence was visible in the crater, volcanic blocks rolled 500-800 m down Tungurahua's flanks, and continuous ash emissions were followed by three small explosions. A pilot reported observing a W-drifting steam-and-ash column ~2 km above the volcano's summit. Also, an explosion during the afternoon produced an ash cloud that rose to 2 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 June-11 June 2002

During 4-10 June, continuous degassing occurred at Tungurahua, accompanied by nearly continuous volcanic tremor, long-period earthquakes, and occasional small-to-moderate explosions sometimes preceeded by volcano-tectonic events. A moderate explosion on 4 June deposited ash in the sectors of Pillate and San Juan. Strombolian activity was visible during the night of 9 June.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


29 May-4 June 2002

According to IRD, during 27 May-3 June nearly continuous gas, vapor, and ash emissions at Tungurahua sent plumes 1.5-2.5 km above the crater and deposited ash on the volcano's flanks. During the night of 29 May, low-intensity Strombolian activity was observed. After 30 May, more intense ash-rich emissions occurred. On the morning of 2 June a 0.5 mm uncompacted ash layer was deposited at the western base of the volcano. During the week, there was an abrupt increase in the number of daily explosions, which gradually decreased. Also, several explosions were observed sending ash plumes to 3-4 km above the crater and incandescent ballistic blocks as far as 2 km from the vent. According to IG, heavy rainfall generated a small lahar on 3 June that traveled NW. On the same day at 1321 a long-period earthquake was associated with an eruption that sent an ash cloud to a height of 2 km above the volcano. Ash fell to the NW.

Sources: Institut de Recherche pour le Développement (IRD), Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 May-28 May 2002

During 22-27 May, emissions of gas, steam, and ash continued at Tungurahua. On the 22nd a small explosion produced an ash cloud to a height of 2 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


15 May-21 May 2002

During 14-21 May, emissions of gas, steam, and ash continued at Tungurahua. On 14 May an eruption produced a steam-and-ash plume that rose 1.5 km above the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


8 May-14 May 2002

During 6-13 May, emissions of gas, steam, and ash continued at Tungurahua. On 12 May at 0116 a small eruption produced a W-drifting column of steam, gas, and ash that rose to an unknown height. Incandescent material was erupted that travelled 1.5 km down the volcano's flank. Three other small explosions occurred on the 12th and four occurred on the 13th. Relatively large amounts of ash fell to the NW in the town of Ambato on the 13th.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


1 May-7 May 2002

During 30 April-5 May, emissions of gas, steam, and ash continued at Tungurahua. Volcanic clouds rose to 1 km and drifted towards the W. On 1 May at 0400 a lahar traveled down the volcano's flank, blocking the highway near Pampas.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


24 April-30 April 2002

During 23-29 April, emissions of gas, steam, and ash continued at Tungurahua. Three lahars occurred on 28 April.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


17 April-23 April 2002

During 17-23 April, emissions of gas, steam, and ash continued at Tungurahua. A small ash cloud was visible on satellite imagery on 19 April.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


10 April-16 April 2002

During 10-13 April, small emissions of gas, steam, and ash rose 500 m above Tungurahua. On the 11th a small amount of ash fell in the N-flank resort town of Baños.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


3 April-9 April 2002

During 3-9 April, emissions of gas, steam, and ash continued at Tungurahua. A new period of tremor began at the volcano on 2 April. On 7 April gas-and-ash clouds were visible rising 1-2 km above the volcano and drifting mainly to the N. The same day around noon a lahar travelled N, blocking the Ambato-Baños route.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), El Comercio


27 March-2 April 2002

During 26 March-2 April, emissions of gas, steam, and ash continued at Tungurahua. According to a news article, IG stated that on 28 March ash from an emission at 1843 rose 3 km a.s.l., drifted to the NNW, and "was spotted" in the towns of of Pillate, Cotalo, and Pelileo.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Zwire.com


20 March-26 March 2002

During 20-25 March, several emissions of gas, steam, and ash occurred at Tungurahua. Strombolian activity occurred during the evening of 19 March; volcanic blocks were hurled 200 m and rolled down the volcano's NW flank, ash was emitted, incandescent material was visible, and roaring was heard. Ash fell in the sector of Chacauco. According to IG, on 21 March eruptions produced gas clouds with a moderate amount of ash that rose as high as 3 km above the volcano and drifted to the W.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


13 March-19 March 2002

According to IRD-IG, during 4-6 March Strombolian activity at Tungurahua was accompanied by gas emissions that reached 1-2 km above the volcano. Incandescent ejecta rose 50-200 m above the western crater rim, tephra fell around the crater, and blocks rolled down the volcano's upper flanks. On the 5th and 6th small amounts of fine ash fell to the NW in Patate Valley and in Ambato Valley. An explosion on the 6th at 1524 produced an ash cloud that rose 4 km above the crater and drifted to the N. During 7-9 March, volcanism was less intense. On the 10th volcanism increased; small amounts of ash fell on the volcano's W flank, and incandescent projections reached ~100 m above the crater. IG reported that on 12 March a gas plume, with little ash content, rose 2 km above the volcano and drifted to the W.

Sources: Institut de Recherche pour le Développement (IRD), Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


6 March-12 March 2002

During 6-11 March, several small emissions of gas, steam, and ash occurred at Tungurahua. On 11 March an eruption produced a gas-and-ash cloud that rose ~2 km above the volcano and drifted to the SW. During the evening, incandescent volcanic blocks were visible near the volcano's crater.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


27 February-5 March 2002

During 27 February-2 March abundant emissions of steam, gas, and small amounts of ash occurred at Tungurahua, as well as sporadic explosions. The highest rising ash cloud was produced by an explosion on 27 February at 0741. The cloud reached a height of ~2 km above the volcano and drifted to W. During some evenings incandescent material was visible rolling down the flanks of the volcano; on 2 March material extended ~500 m.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


20 February-26 February 2002

During 19-24 February relatively low-intensity Strombolian activity continued at Tungurahua. In addition, there were several emissions of steam, gas, and ash. On the afternoon of 19 February a mixture of rain and ash fell in the Puela sector, and a small lahar travelled W to the Chontapamba sector. That evening, low-intensity Strombolian activity was observed. On the 20th at 2127, incandescent blocks were emitted that rolled down the flank to the Refugio de Pondoa. The next day during 0752-0905 ash columns reached 2 km above the volcano and drifted to the SW. Since 5 September 2000 the volcano has been at Alert Level Yellow for the town of Baños and at Orange for the rest of the population in the high-risk zone.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


13 February-19 February 2002

On the evening of 13 February Strombolian activity occurred at Tungurahua; incandescent volcanic blocks were hurled up to 1 km from the volcano's crater. The following day a consistent steam plume rose to 1 km above the volcano. Around 15-16 February explosive activity decreased, and then increased on the 17th.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


6 February-12 February 2002

During 6-11 February, several emissions of steam and ash occurred at Tungurahua. The highest rising ash cloud was produced by an eruption on 6 February at 0935; it reportedly reached a height of ~3 km above the volcano and drifted to the N and NE. On the same day lahars travelled to the sector of La Pampas. Nearly continuous gas-and-ash emissions rose to 1 km above the volcano on the 6th and 8th, and to 3 km on the 10th.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


30 January-5 February 2002

During 30 January-5 February, several emissions of steam with small amounts of ash occurred at Tungurahua. The highest rising ash cloud was produced by an eruption on 3 February at 1326 and reportedly reached a height of ~3 km above the volcano. Ash sporadically fell in Pillate and Ambato. Ash from emissions on 4 February fell in Baños, Pillate, and Ambato.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


23 January-29 January 2002

Based on information from IG, the WashingtonVAAC reported that during 23-29 January several small ash emissions occurred at Tungurahua. The highest reported cloud rose to a height of ~7.5 km a.s.l. During 15-23 January incandescence was visible in the crater.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


16 January-22 January 2002

During the week of 16-22 January several emissions of steam, gas, and small amounts of ash occurred at Tungurahua. The highest plumes visible on satellite imagery rose ~7.6 km a.s.l. on 16 and 22 January. During 15-16 January intense incandescence was visible in the crater. Seismicity consisted of long-period earthquakes and seismic signals associated with steam-and-ash emissions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


9 January-15 January 2002

Several eruptions of steam and ash occurred during the week at Tungurahua. An eruption on 8 January produced a steam column with a low ash concentration to a height of 1 km above the crater and deposited small amounts of ash in the towns of Baños, Guaranda, and Chimborazo. The next day a 1-km-high steam-and-ash cloud drifted to the W, depositing small amounts of ash in the vicinity of Juive on the NW flank of the volcano. Heavy rainfall generated lahars on 9 January that traveled down the volcano's W flank.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


2 January-8 January 2002

According to the Washington VAAC, there were several reports of ash emissions during the week. The highest reported ash cloud reached a height of ~10 km a.s.l. on 4 December at 1719.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 December-1 January 2002

During the report week, volcanic activity increased at Tungurahua. Eruptions began on 27 December at 1006 and 1427 that produced W-drifting gas-and-ash clouds to heights of 2 and 1 km above the volcano, respectively. A mudflow was reported on 29 December at 2342 travelling to the NW via Juive Grande Gorge. It affected the Pampa and Los Pájaros sectors. On 30 December at 0023 a seismic signal associated with an explosion was recorded, but the explosion was not observed due to cloudy conditions. Until 1500 ashfall was reported in the sectors of Guadalupe and Patate and may have also fallen to the W of the volcano. IG issued a SIGMET stating that at 0027 ash from the explosion rose to ~15 km. No ash was visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 December-25 December 2001

Volcanic activity remained relatively low at Tungurahua. Several steam emissions occurred during the week, with some accompanied by sporadic pulses of gas and ash. Steam clouds rose to a maximum height of 1 km above the volcano. Seismicity was dominated by long-period earthquakes. IG warned that mud flows could be generated at any time.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


12 December-18 December 2001

On 14 December and the morning of 16 December lahars travelled down Tungurahua's flanks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


5 December-11 December 2001

Observations at Tungurahua during 26 November to 3 December revealed that volcanic activity was low. A fairly continuous pulsating plume of steam and gas was emitted from the summit crater. On 2 December five small ash emissions occurred in 70 minutes that reached 500-1,000 m above the crater and drifted to the N. Ash emissions were also observed during 2-3 December. Seismic activity was dominated by long period events, with about 15-40 occurring per day.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


28 November-4 December 2001

Volcanic activity was relatively low at Tungurahua during the week. Based on information from IG, the Washington VAAC reported that a small ash emission occurred on 2 December at 1140. The ash cloud was not visible on satellite imagery; it is believed to have remained near summit level.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


14 November-20 November 2001

Several steam, gas, and ash emissions occurred at Tungurahua during the week. On 18 and 19 November emissions with significant amounts of ash were observed rising to 2 km above the volcano as they drifted to the W and NW. IG warned that mud flows could be generated by ash on the flanks mixing with rain during periods of heavy rainfall.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


7 November-13 November 2001

On 11 November two emissions of steam-and-ash occurred and the clouds drifted to the W; at 1050 a cloud rose 1 km above the volcano, and at 1352 a cloud rose 3 km. The Alert Level remained at Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone, as it has since 5 September 2000.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


31 October-6 November 2001

IG reported that during the morning of 1 November three emissions of steam and ash were observed rising 1 to 2 km above Tungurahua's summit and drifting to the E and NE. According to the Washington VAAC, no ash was visible on satellite imagery at 0545, although any significant ash would have been visible. On 2 November there was a small increase in the number of long-period events and steam-and-ash emissions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), El Comercio


24 October-30 October 2001

During the week, relatively low volcanic activity continued at Tungurahua. Several steam-and-ash emissions occurred. The night of 23 October ash emissions were observed rising 1 km above the volcano's summit. During 23 to 25 October there was a small increase in the number of long-period earthquakes and steam-and-ash emissions. On 26 October a hot spot was visible at Tungurahua's summit on thermal satellite imagery.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


17 October-23 October 2001

For about three weeks seismic and volcanic activity was relatively low at Tungurahua, consisting of long-period earthquakes, fumarolic activity, and no explosive activity.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


10 October-16 October 2001

The IG reported to the Washington VAAC that ash was visible ~800 m above the volcano on 14 October at 1736. No ash was visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


26 September-2 October 2001

On 24 September at 1500 an eruption at Tungurahua produced an ash cloud that rose ~2 km above the volcano and drifted to the W and SW. Roaring and the sound of rockfalls were heard in several towns near the volcano. An eruption on 25 September at 1230 produced a mushroom-shaped ash cloud that rose 5 km above the volcano. The lower portion of the plume drifted to the NW, while the higher portion remained fixed. Ash fell in the town of Cotaló. During the evening of the 25th Strombolian activity was observed, with rockfalls and incandescent volcanic fragments travelling to the W and NW flanks of the volcano. After the eruption volcanic activity consisted of low-level emissions of steam, gas, and ash. Small amounts of ash fell in southern Quero.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


19 September-25 September 2001

During the week several moderate-sized explosions and low-level emissions of ash and gas occurred. An explosion on 20 September at 1044 produced an ash cloud that rose to 2 km above the volcano and drifted to the WSW. The explosion was accompanied by loud roaring and the sound of rockfalls. Small amounts of ash fell in Pillate, Juive, and Runtún. The explosion was preceded by tremor for approximately 3 hours. On 21 September at 1625 another moderate-sized explosion produced an ash cloud that rose to 3 km above the volcano's summit and drifted to the NW. During the night incandescence was visible at the volcano's crater.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


12 September-18 September 2001

During the week volcanic activity at Tungurahua was characterized by a large number of long-period earthquakes, near-summit ash-and-gas emissions, and sporadic small-to-moderate explosions. The highest ash cloud reached ~8 km a.s.l. On 11 September, and to a lesser extent on 12 September, ash fell to the N of the volcano in the towns of Pondoa, Runtun, and Baños. In addition, ash fell to the SW in Quero and Penipe, and mud flows were reported in Penipe. Explosions on 13 September deposited ash to the W of the volcano, affecting the towns of Juive, Cotalo, and Bibao. On the 15th ash fell to the SW in Riobamba and Penipe. On 16 September incandescent material was emitted from the volcano along with ash and gas. The Alert Level remained at Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone, as it has since 5 September 2000.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


5 September-11 September 2001

Several small-to-moderate eruptions occurred at Tungurahua during the week. The highest ash cloud reported was observed by a pilot and occurred on 8 September at 0828, rose ~10.5 km a.s.l., and drifted to the SW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


29 August-4 September 2001

Small emissions that contained minor amounts of ash took place during the week. The highest ash cloud reported occurred on 3 September, rose to ~5.8 km, and drifted to the W.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


22 August-28 August 2001

The Washington VAAC reported that nearly continuous ash emissions had occurred at Tungurahua since 6 August, but extensive cloudiness prohibited ash-cloud detection in satellite imagery. According to the Guayaquil MWO, a new eruption on 24 August at 1755 produced an ash cloud that rose to ~6 km and drifted E to SE. The same day IG reported that ash was emitted to 6-7.6 km.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


15 August-21 August 2001

The series of eruptions that began at Tungurahua on 6 August continued during the week. Seismic activity was characterized by many long-period earthquakes and seismic signals that represented ash emissions. Several sporadic explosions occurred, with the largest explosion beginning on 15 August at 2231. The eruption produced an ash cloud that rose to 12.2 km a.s.l. IG reported that on 17 August volcanic activity increased slightly and incandescent material was ejected up to 1 km W of the crater. According to news reports, as of 15 August ash affected more than 23,000 people, blanketed approximately 89,000 acres of crops, and killed an undetermined number of livestock. The Alert Level remained at Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone, as it has since 5 September 2000.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Associated Press, Reuters


8 August-14 August 2001

Ongoing eruptions occurred at Tungurahua since at least 6 August at 0703, sending steam-and-ash clouds to 7.5-11.6 km a.s.l. The ash clouds primarily drifted towards the W. On 13 August three particularly strong emissions occurred at about 0630, 1200, and 1315. Afterward, two distinct areas of ash were visible in satellite imagery; one contained ash from the strong emissions, rose to ~11.6 km a.s.l. and drifted to the E; the other ash cloud was fed from continuous emissions and possibly rose to ~10 km a.s.l. and drifted to the SW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC), Associated Press


1 August-7 August 2001

IG reported that during 2 August until at least 3 August there was an increase in volcanic activity at Tungurahua. Continuous tremor began on 3 August at 1400 that may have been associated with continuous ash emission. In addition, the Washington VAAC reported that several eruptions occurred during the week, with the largest eruption on 5 August at 1700 producing an ash cloud that rose to ~12.5 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


25 July-31 July 2001

Several small-to-moderate eruptions occurred at Tungurahua during the week. The Washington VAAC reported that the highest ash cloud was produced from an eruption on 25 July at 0604. The ash cloud rose ~9 km a.s.l. and drifted to the SW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


18 July-24 July 2001

During the week heavy rain remobilized ash deposited on the flanks of the volcano, generating lahars, and several small-to-moderate eruptions produced ash clouds. On 19 July lahars that traveled down the W flank of the volcano reached the Baños-Riobamba highway. The Washington VAAC reported that one of the larger eruptions during the week occurred on 20 July at 2104 and produced an ash cloud that rose to ~7.9 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


11 July-17 July 2001

During the week several small-to-moderate eruptions produced ash clouds. The largest eruption, on 12 July, produced an ash cloud that rose to ~8.3 km a.s.l. and drifted W to NW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


4 July-10 July 2001

During 3-8 July several small-to-moderate eruptions produced ash clouds. One of the larger eruptions occurred on 5 July at 1310, producing an ash cloud that a pilot reported rose to ~7.6 km a.s.l. However, satellite imagery and additional information suggested that the dense SE-drifting ash cloud rose to ~9 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


27 June-3 July 2001

According to reports from IG, about one small explosion per day has occurred at Tungurahua since the explosion on 17 June produced an ash cloud that rose to 7 km above the summit. The explosions have usually occurred with no warning, and light ash fall has frequently fallen to the W of the volcano, often damaging crops. The Washington VAAC reported that during the week the IG stated that seismic activity on 28 June at 1824 suggested that an eruption may have produced an ash cloud that rose to 7 km a.s.l. The ash cloud was not visible in satellite imagery. On 3 July at 0715 the Washington VAAC issued a report that a pilot observed W-drifting ash over the volcano between 5.8 and 7.6 km a.s.l.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


20 June-26 June 2001

Based on information from the IG, the Washington VAAC reported that on 22 June at 0630 and 0652 eruptions sent ash clouds to 5.8 and 8.8 km a.s.l., respectively. No ash was visible on satellite imagery. Small explosions on 25 June at 0138 and 1328 produced ash clouds that rose ~6 km a.s.l and drifted to the W. Small amounts of ash were deposited in the town of Ambato, ~40 km NW of the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


13 June-19 June 2001

Several small eruptions produced ash clouds that rose to a maximum height of ~9.7 km. The IG reported that the number of long-period earthquakes and the emission of gas and ash had increased since the end of April. They warned that heavy rain could remobilize ash on the flanks of the volcano, generating dangerous lahars.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


6 June-12 June 2001

A SIGMET from the Guayaquil MWO noted that the IG reported ash to 7 km a.s.l. moving W on 5 June at 1200. Considerable cloudiness over and around the summit made it difficult to detect any ash in satellite imagery. Similar reports were made on 6 June at 2324 and on 11 June at 1602, but no estimates of ash cloud heights were possible. Based on the seismic record, the 11 June explosion was a small event. A lahar was also observed on the morning of 11 June that moved down the Quebrada Achupashal.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


30 May-5 June 2001

Volcanic activity increased at Tungurahua. A large number of long-period earthquakes accompanied several small eruptions and near-continuous gas-and-ash emission. The IG reported that an eruption on 31 May at 2120 produced an ash cloud that rose up to ~7.9 km a.s.l. and drifted to the W. Incandescent blocks were ejected during the eruption, and an acoustic wave that sounded like a cannon shot was heard several km away from the volcano. Eruptions also occurred on 29 May at 2012 that sent ash to a height of ~8.2 km a.s.l., on 30 May at 1211 (ash plume to an unknown height), and on 2 June at 1709 with an ash plume to ~7.9 km. Incandescent material was visible in the crater, and IG warned that heavy rain could remobilize ash and generate lahars.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


23 May-29 May 2001

Based on information from the IG, the Washington VAAC reported that on 26 May at 2215 ash from an eruption of Tungurahua was observed at a height of ~7 km a.s.l. drifting to the NE. Extensive cloudiness in the area prohibited ash cloud detection on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


16 May-22 May 2001

Volcanic activity increased slightly at Tungurahua during the week. On 15 May several small eruptions occurred, with the largest sending ash up to 3 km above the summit. Light ash fell in the towns of Cotaló and Bilbao. The Washington VAAC reported that an eruption that began around 1830 on 17 May sent an ash cloud to ~9 km a.s.l. that drifted to the SW. According to IG on 17 and 18 May Tungurahua was not visible due to cloudy conditions, but intense activity was indicated by the high number of long-period earthquakes and seismic signals that may have been associated with eruptions. At 0615 on 19 May an eruption produced an ash cloud that rose ~6.7 km a.s.l. IG warned that lahars might be generated if rainfall mixed with ash deposited on the upper W flanks of the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


9 May-15 May 2001

Heavy rainfall in the vicinity of Tungurahua caused the remobilization of ash deposited on the upper flanks of the volcano, producing several lahars. Lahars traveled down the Cusúa, Basural, Mandur, ún, and Ulba gorges. Lahars caused the closing of the Baños-Riobamba highway and blocked a route to the town of Baños.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


2 May-8 May 2001

Moderate levels of volcanic activity continued at Tungurahua, with small steam-and-ash transmissions occurring. Seismic activity indicated that a lahar may have traveled down the flanks of the volcano on 3 May.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


25 April-1 May 2001

Based on information from the IG, the Washington VAAC reported that several small eruptions occurred at Tungurahua and that lahars were active in several sectors of the volcano. At 1600 on 25 April a pilot reported that ash was visible over the volcano at an altitude of ~7 km. Seismic activity indicated that brief eruptions occurred at 1230 on 28 April and at 1130 on 29 April, but extensive cloudiness prevented observations of the ash clouds. On 29 and 30 April lahars traveled to the Pampas, Cusuá, Hacienda, and Achupashal sectors and the river levels rose in the Ulba and Mandur sectors. The lahars in the Pampas sector blocked the Pelileo-Baños channel during 0710 to 1100 on 29 April and destroyed the highway. The IG warned that rainy conditions may cause more lahars and rising river levels near the volcano.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


18 April-24 April 2001

IG stated that during the night of 20 April incandescence was visible in the interior of the dome and the next day a steam column rose a short distance above the summit. IG warned that residents near the volcano should be alert to the possibility of mud flows forming during periods of heavy rain. Since 5 September 2000, the Alert Level has been at Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


11 April-17 April 2001

Based on information from IG, the Washington VAAC reported that two small eruptions produced ash clouds that rose ~7 km a.s.l. and blew towards the W; one at 1530 on 14 April, and the other at 1140 on 15 April. The ash clouds were not visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


28 March-3 April 2001

Based on information from the IG, the Washington VAAC reported that a small emission of ash occurred at 1400 on 29 March, producing an ash cloud that rose ~6 km and drifted to the W. Another small eruption occurred at 1746 on 2 April. Neither cloud was visible on GOES-8 imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


21 March-27 March 2001

During the week of 18-24 March seismicity and fumarolic activity at Tungurahua continued. The IG reported that at 1915 on 22 March an eruption column with an incandescent point rose to a height of 2 km and lasted 10 minutes. Another eruption on 23 March at 1014 lasted for 30 minutes, sending a column 2 km high that moved NW. Pilot reports indicated that the plume reached an altitude of 6 km. At night a point of incandescence in the crater was observed again. Extensive meteorological clouds prevented the Washington VAAC from obtaining good satellite imagery of the 22 and 23 March plumes.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


14 March-20 March 2001

During the week several small eruptions occurred at Tungurahua and seismic activity was at high levels. Based on information from the IG, the Washington VAAC reported that an ash emission at 1608 on 13 March produced an ash cloud that rose to ~9.6 km a.s.l. and drifted to the NW. The IG stated that the transmission lasted ~10 minutes and that light ash fell in the towns of Cotalo and Pillaro. At 1415 on 15 March an eruption produced an ash cloud that rose ~3.2 km above the volcano. An ash emission occurred at 1756 on 16 March that rose to 8.8 km a.s.l. and drifted to the ENE.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


21 February-27 February 2001

The IG reported that at 1056 on 21 February an eruption sent an ash cloud to ~8.8 km a.s.l. that drifted to the NW. The ash cloud was not visible on the Washington VAAC's GOES-8 imagery. The IG reminded residents near the volcano that strong rains in the area may remobilize ash and generate lahars.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


14 February-20 February 2001

The IG reported that at 1050 on 19 February lahars were registered at a seismic station. The lahars traveled down the NW flank of the volcano via the Cusúa Gorge. The same day a steam column rose 1 km above the summit and drifted to the NE.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


17 January-23 January 2001

Based on information from the IG, the Washington VAAC reported that an eruption occurred at 1840 on 18 January. It sent an ash cloud to 6.7 km a.s.l. that blew to the W. The ash cloud was not visible on satellite imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


10 January-16 January 2001

The IG reported that since 3 January, Tungurahua has had an increase in vapor-and-ash emissions from its 300-m-diameter summit crater. Planes have observed the ash plumes up to 7 km altitude. From the Guadalupe observatory, 11 km N of the cone, ash-laden columns to 3-4 km altitude were observed. No new explosive activity or incandescence has been seen since 22 October 2000. SO2 values, which had been at about 1,000 metric tons/day (t/d) have now risen to 2,000-2,400 t/d. Seismicity remains very low. New fumaroles have been observed since late November at 4,400 m elevation on the NW flank.

Based on reports from the IG, the Washington VAAC issued aviation notices of ash over the volcano on the afternoon of 10 January to an altitude of 6.4 km. Cloudiness made satellite observations difficult, but a pilot reported ash to 7 km altitude over the volcano in the early afternoon of the 11th.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


3 January-9 January 2001

The IG reported to the Washington VAAC that ash clouds were observed above the summit of Tungurahua several times during the week, reaching a maximum height of 7.9 km a.s.l. No ash was visible in GOES-8 imagery. The IG also reported that a slight increase in volcanic activity on 3 and 4 January was marked by moderate-sized ash-bearing emissions.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


20 December-26 December 2000

The IG reported that on 21 December an ash cloud was observed over the summit of Tungurahua at a height of ~5.8 km a.s.l. According to the Washington VAAC, the ash was not visible on GOES-8 imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


13 December-19 December 2000

The IG reported that at 1415 on 14 December an ash cloud was observed at an altitude of ~5.5 km a.s.l. near Tungurahua's summit, moving to the NE. No ash was visible in GOES 8 imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


6 December-12 December 2000

The IG reported an ash cloud at ~5 km a.s.l. (near-summit level) on 9 December. The Washington VAAC used GOES-8 imagery to confirm that the thin ash cloud was moving to the SW.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


29 November-5 December 2000

The IG reported that seismicity and explosive activity were at low levels during the week. A gas column was emitted sporadically through the week, and reached an altitude of 300-500 m above the volcano. As of 5 December the period of low activity had continued at Tungurahua for 43 days.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


22 November-28 November 2000

The IG reported that seismicity and explosive activity were at low levels during the week. On 27 November small ash-and-gas discharges reached a maximum altitude of 500 m above the summit.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


15 November-21 November 2000

The IG reported that seismicity and explosive activity were at low levels during the week, but by 20 November there was an increase in seismicity.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


8 November-14 November 2000

The IG reported that seismicity and explosive activity were at low levels during the week. The Washington VAAC reported that on 13 November a small ash cloud, which was near summit level and blown to the SE, was visible in GOES-8 imagery.

Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)


1 November-7 November 2000

The IG reported that seismicity and explosive activity were at low levels during the week. A gas column was almost continuously emitted from Tungurahua, and reached a maximum altitude of 500 m above the crater. Since 5 September 2000, the volcano has been at Alert Level Yellow in the town of Baños and at Orange for the rest of the population in the high-risk zone.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)


Summary of eruption dates and Volcanic Explosivity Indices (VEI).

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
2010 Nov 22 2014 Feb 27 (continuing) Confirmed 3 Historical Observations
2010 Jan 1 2010 Jul 29 Confirmed 3 Historical Observations
1999 Oct 5 2009 Jul 8 ± 7 days Confirmed 3 Historical Observations
[ 1993 May 6 ] [ 1993 May 6 ] Uncertain 1  
[ 1944 ] [ Unknown ] Uncertain 2  
1916 Mar 3 1925 Dec 1 ± 30 days Confirmed 4 Historical Observations
[ 1900 ] [ Unknown ] Uncertain 2  
1886 Jan 11 1888 ± 1 years Confirmed 4 Historical Observations
1885 Jan (?) 1885 Oct 16 Confirmed 2 Historical Observations
1857 Sep 10 (?) Unknown Confirmed 2 Historical Observations
[ 1781 ] [ Unknown ] Uncertain 2  
[ 1777 ] [ Unknown ] Uncertain 2  
1776 Jan 3 Unknown Confirmed 2 Historical Observations
1773 Feb 4 1773 Jul (?) Confirmed 3 Historical Observations P2 tephra
[ 1757 ] [ Unknown ] Uncertain 2  
1644 1646 (?) Confirmed 2 Historical Observations
1640 1641 Confirmed 3 Historical Observations
1557 Unknown Confirmed 2 Historical Observations
1350 ± 50 years Unknown Confirmed 3 Radiocarbon (corrected)
1250 ± 50 years Unknown Confirmed   Radiocarbon (corrected)
1030 ± 75 years Unknown Confirmed   Radiocarbon (uncorrected) Tephra layer F
0800 (?) Unknown Confirmed   Radiocarbon (uncorrected)
0730 ± 200 years Unknown Confirmed 4 Radiocarbon (uncorrected) P1 tephra unit
0600 (?) Unknown Confirmed 3 Radiocarbon (uncorrected)
0480 ± 75 years Unknown Confirmed   Radiocarbon (uncorrected)
0350 (?) Unknown Confirmed 3 Radiocarbon (uncorrected)
0200 (?) Unknown Confirmed   Radiocarbon (uncorrected)
0100 (?) Unknown Confirmed 3 Radiocarbon (uncorrected)
0050 BCE (?) Unknown Confirmed 3 Radiocarbon (uncorrected)
0100 BCE (?) Unknown Confirmed 3 Radiocarbon (uncorrected)
0270 BCE ± 100 years Unknown Confirmed   Radiocarbon (uncorrected)
0500 BCE (?) Unknown Confirmed 3 Radiocarbon (uncorrected)
1010 BCE ± 100 years Unknown Confirmed 5 Radiocarbon (uncorrected)
7750 BCE (?) Unknown Confirmed 4 Radiocarbon (uncorrected)

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title. Additional discussion of data sources can be found under Volcano Data Criteria.

Almeida E, Ramon P, 1991. Las erupciones historicas del Volcan Tungurahua. Bol Geol Ecuatoriano, 2: 89-138.

Arellano S R, Hall M, Samaniego P, Le Pennec J-L, Ruiz A, Molina I, Yepes H, 2008. Degassing patterns of Tungurahua Volcano (Ecuador) during the 1999-2006 eruptive period, inferred from remote spectroscopic measurements of SO2 emissions. J Volc Geotherm Res, 176: 151-162.

Fee D, Garces M, Steffke A, 2010. Infrasound from Tungurahua Volcano 2006-2008: Strombolian to Plinian eruptive activity. J Volc Geotherm Res, 193: 67-81.

Hall M L, 1977. El Volcanismo en El Ecuador. Quito: Biblioteca Ecuador, 120 p.

Hall M L, 1992. . (pers. comm.).

Hall M L, Robin C, Beate B, Mothes P, Monzier M, 1999. Tungurahua volcano, Ecuador: structure, eruptive history and hazards. J Volc Geotherm Res, 91: 1-21.

Hall M L, Vera R, 1985. La actividad volcanica del volcan Tungurahua: sus peligros y sus riesgos volcanicos. Rev Politecnica, Quito, 10: 91-144.

Hantke G, Parodi I, 1966. Colombia, Ecuador and Peru. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 19: 1-73.

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior..

Johnson J B, Aster R C, Ruiz M C, Malone S D, McChesney P J, Lees J M, Kyle P R, 2003. Interpretation and utility of infrasonic records from erupting volcanoes. J Volc Geotherm Res, 121: 15-63.

Le Pennec J-L, Hall M L, Robin C, Bartomioli E, 2006. Tungurahua volcano: late Holocene activity. Cities on Volcanoes 4, Quito, Ecuador, 23-27 Jan, 2006, Field trip A1: 1-23.

Le Pennec J-L, Jaya D, Samaniego P, Ramon P, Moreno Yanez S, Egred J, van der Plicht J, 2008. The AD 1300-1700 eruptive periods at Tungurahua volcano, Ecuador, revealed by historical narratives, stratigraphy and radiocarbon dating. J Volc Geotherm Res, 176: 70-81.

Samaniego P, Eissen J-P, Le Pennec J-L, Hall M L, Monzier M, Mothes P, Ramon P, Robin C, Egred J, Molina I, Yepes H, 2003. Los peligros volcanicos asociados con el Tungurahua. Inst Geofis Escuela Politecnica Nac, Inst Recherche Devel, 1: 1-108.

Steffke A M, Fee D, Garces M, Harris A, 2010. Eruption chronologies, plume heights and eruption styles at Tungurahua Volcano: Integrating remote sensing techniques and infrasound. J Volc Geotherm Res, 193: 143-160.

Tungurahua, a steep-sided andesitic-dacitic stratovolcano that towers more than 3 km above its northern base, is one of Ecuador's most active volcanoes. Three major volcanic edifices have been sequentially constructed since the mid-Pleistocene over a basement of metamorphic rocks. Tungurahua II was built within the past 14,000 years following the collapse of the initial edifice. Tungurahua II itself collapsed about 3000 years ago and produced a large debris-avalanche deposit and a horseshoe-shaped caldera open to the west, inside which the modern glacier-capped stratovolcano (Tungurahua III) was constructed. Historical eruptions have all originated from the summit crater. They have been accompanied by strong explosions and sometimes by pyroclastic flows and lava flows that reached populated areas at the volcano's base. Prior to a long-term eruption beginning in 1999 that caused the temporary evacuation of the city of Baños at the foot of the volcano, the last major eruption had occurred from 1916 to 1918, although minor activity continued until 1925.