Veniaminof

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  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 56.17°N
  • 159.38°W

  • 2507 m
    8223 ft

  • 312070
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

16 October-22 October 2013

Lava effusion from Veniaminof's intracaldera cone resumed on 6 October, prompting AVO to raise the Volcano Alert Level to Watch and the Aviation Color code to Orange.

On 17 October AVO noted that seismicity had decreased during the previous week and satellite observations during periods of clear weather showed no evidence of eruptive activity. The Aviation Color Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory. Seismicity remained above background levels during 17-22 October.

Source: US Geological Survey Alaska Volcano Observatory (AVO)



 Available Weekly Reports


2013: June | July | August | September | October
2009: May
2008: February | April
2006: March | April
2005: January | February | March | September | November
2004: February | April | May | June | July | August | September | October | December
2003: January | February | March | April
2002: September | October | November | December


16 October-22 October 2013

Lava effusion from Veniaminof's intracaldera cone resumed on 6 October, prompting AVO to raise the Volcano Alert Level to Watch and the Aviation Color code to Orange.

On 17 October AVO noted that seismicity had decreased during the previous week and satellite observations during periods of clear weather showed no evidence of eruptive activity. The Aviation Color Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory. Seismicity remained above background levels during 17-22 October.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


18 September-24 September 2013

On 20 September AVO reported that, based on a decrease in seismicity at Veniaminof and no eruptive activity observed by satellite or the web camera over the previous week, the Aviation Color Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory. Low-level seismic tremor continued during 21-24 September.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


11 September-17 September 2013

AVO reported continuous seismic tremor at Veniaminof during 11-17 September, and elevated surface temperatures detected in satellite images that were consistent with lava effusion and fountaining. On 11 September a diffuse steam plume possibly containing ash was recorded by the web cam in Perryville, 32 km SSE. Weak thermal anomalies and decreased levels of tremor during 14-16 September possibly indicated ongoing but diminished lava effusion. No unusual or eruptive activity was observed in web cam images through 17 September. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


4 September-10 September 2013

AVO reported continuous seismic tremor at Veniaminof during 4-10 September, and elevated surface temperatures detected in satellite images consistent with lava effusion and fountaining. Cloud cover sometimes prevented web cam views (from Perryville, 32 km SSE) of the intracaldera cone, although on 4 September a diffuse ash plume was observed rising several hundred feet above the cone and drifting E. On 7 September the web cam recorded a plume more steam-rich than in recent days. No ash emissions were visible in web cam images on 10 September. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


28 August-3 September 2013

AVO reported that during 27-29 August seismicity at Veniaminof was characterized by discreet episodic tremor bursts, likely associated with lava effusion and minor ash emissions. Satellite images detected prominent thermal anomalies at the intracaldera cone. Activity increased on 30 August and was some of the strongest detected since the eruption began in early June; intense seismicity, lava fountaining, and ash emissions to 4.6-6.1 km (15,000-20,000 ft) a.s.l. were observed. Ash plumes drifted SE and caused ashfall in areas downwind including Perryville (32 km SSE). Elevated and continuous tremor persisted during 31 August-3 September; cloud cover and fog obscured web-cam and satellite views. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


21 August-27 August 2013

AVO reported that on 20 August residents of Perryville (32 km SSE) reported hearing loud explosions coming from Veniaminof, and air waves were detected by infrasound equipment in Dillingham (322 km NE). Trace amounts of ash fell in Perryville. During 20-21 August seismic activity at Veniaminof decreased; seismicity became more episodic and fluctuated between periods of relative quiet and short periods of low-level, nearly continuous tremor. Minor ash-and-steam emissions likely continued, but effusion of lava may have slowed down or possibly stopped. Elevated surface temperatures at the cone were observed in satellite data.

Seismicity during 22-26 August remained low; small ash bursts were probably produced during short periods of elevated tremor. During 23-26 August satellite data showed weak thermal anomalies at the intracaldera cone and very minor ash emissions were occasionally observed in web camera views from Perryville. During 26-27 August seismicity was characterized by nearly continuous, gradually fluctuating tremor possibly indicative of low-level ash emission and probable lava effusion. Satellite images detected a thermal signal at the intracaldera cone. Web camera views from Perryville showed a slightly more robust ash plume, extending ESE beyond the caldera rim. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


14 August-20 August 2013

AVO reported that during 13-15 August seismic tremor at Veniaminof was high, and persistent elevated surface temperatures consistent with lava effusion were visible on satellite imagery. During 16-17 August the high levels of tremor became sustained; seismicity remained high through 20 August. Very high surface temperatures were detected in images during 16-17 August; only weak thermal signals were evident through the cloud cover in satellite data during 17-18 August. Clear views on 18 August from the FAA web-camera in Perryville (32 km SSE) showed minor ash emissions. During a helicopter overflight on 19 August geologists observed two active lava flows from the cone, and lava flowing passively over ice at the foot of the cone. Elevated surface temperatures were detected in satellite data during 19-20 August. Clear web-camera views showed minor ash emissions rising to an altitude of 3.7 (12,000 ft) a.s.l. and drifting W and then SSE, just past the caldera rim. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


7 August-13 August 2013

AVO reported that during 7-11 August seismicity at Veniaminof remained above background levels. Cloud cover obscured views of the cinder cone inside the caldera during 7-8 August. Slightly elevated surface temperatures, consistent with cooling lava flows, were detected in partly cloudy satellite images during 9-10 August. On 11 August cloud cover prevented satellite image views, and web-camera views showed nothing significant. During 11-12 August seismic tremor increased and persistent elevated surface temperatures, consistent with lava effusion, were visible in satellite imagery. The web camera in Perryville (32 km SSE) recorded intermittent steam-and-ash plumes; one on 12 August rose 3.7 km (12,000 ft) a.s.l. and drifted W. Seismic tremor has remained high on 13 August. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


31 July-6 August 2013

AVO reported that the ongoing low-level eruption of Veniaminof, characterized by lava effusion and emissions of minor amounts of ash and steam, continued during 31 July-6 August. Although seismic activity decreased during 31 July-2 August, it still remained above background levels, and small discrete events continued to be detected. Cloud cover prevented satellite image and web-camera views. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


24 July-30 July 2013

AVO reported that the ongoing low-level eruption of Veniaminof, characterized by lava effusion and emissions of minor amounts of ash and steam, continued during 24-30 July, indicated by fluctuating volcanic tremor and occasional small explosions detected by the seismic network. On most days satellite images showed elevated surface temperatures at the cinder cone inside the caldera consistent with lava effusion. On 25 July a pilot reported an ash plume that rose 60-100 m above the cone and drifted almost 25 km S, and a "river of lava" flowing down from the cone. On 27 July a pilot observed an ash emission that rose 300-600 m and drifted NW. A water-rich plume likely containing minor amounts of ash was detected in satellite images drifting NW at an altitude of 4.5 km (15,000 ft) a.s.l. on 29 July. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


17 July-23 July 2013

AVO reported that the ongoing low-level eruption of Veniaminof, characterized by lava effusion and emission of minor amounts of ash and steam, continued during 17-23 July, indicated by nearly continuous volcanic tremor and occasional small explosions detected by the seismic network. On most days satellite images showed elevated surface temperatures at the cinder cone inside the caldera consistent with lava effusion. The web camera in Perryville (32 km SSE) recorded nighttime incandescence and low-level ash-and-steam plumes during 22-23 July. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


10 July-16 July 2013

AVO reported that the ongoing low-level eruption of Veniaminof, characterized by lava effusion and emission of minor amounts of ash and steam, continued during 10-16 July, indicated by nearly continuous volcanic tremor and occasional small explosions detected by the seismic network. Satellite images showed elevated surface temperatures at the cinder cone inside the caldera consistent with lava effusion. Images also showed that most of the lava flows traveled S of the cone a short distance (hundreds of meters). The web camera in Perryville (32 km SSE) recorded very weak emissions of vapor, possibly containing minor amounts of ash, within the caldera during 9-10 July; incandescence from the cone was visible during 10-11 July. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


3 July-9 July 2013

AVO reported that the ongoing low-level eruption of Veniaminof, characterized by lava effusion and emission of minor amounts of ash and steam, continued during 3-9 July, indicated by nearly continuous volcanic tremor and occasional small explosions detected by the seismic network. Satellite images showed elevated surface temperatures at the cinder cone inside the caldera consistent with lava effusion most days. Images also showed that most of the lava flows traveled S of the cone a short distance (hundreds of meters). The web camera in Perryville (32 km SSE) recorded very weak emissions of vapor, possibly containing minor amounts of ash, within the caldera for several hours on 9 July. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


26 June-2 July 2013

AVO reported that the ongoing low-level eruption of Veniaminof, characterized by lava effusion and emission of minor amounts of ash and steam, continued during 26 June-2 July, indicated by nearly continuous volcanic tremor and occasional small explosions detected by the seismic network. Satellite images showed elevated surface temperatures at the cinder cone inside the caldera consistent with lava effusion. During 26-30 June web camera images from Perryville (32 km SSE) showed a small light-colored plume rising above the cone to just above the rim of the caldera, and night time images showed persistent incandescence from the cone. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


19 June-25 June 2013

AVO reported that the eruption of Veniaminof continued during 18-25 June, indicated by volcanic tremor detected by the seismic network. Cloudy weather sometimes prevented views of the caldera, although most days satellite images showed very high elevated surface temperatures at the cinder cone inside the caldera consistent with lava effusion. On 18 June small ash clouds that rose less than 4.6 km (15,000 ft) a.s.l. were intermittently observed in web-camera images. On 24 June satellite images detected elevated surface temperatures and a plume that drifted SW. The web camera recorded a small area of incandescence on the intracaldera cone. On 25 June the web camera showed a light-colored plume rising from the intracaldera cone to just above the caldera rim. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


12 June-18 June 2013

AVO reported that seismic tremor was detected at Veniaminof on 12 June. Elevated surface temperatures were detected in satellite images at 0525 on 13 June, likely indicating an intra-caldera eruption. In response, AVO raised the Volcano Alert Level to Watch and the Aviation Color code to Orange. Seismic tremor continued that day, indicative of low-level effusive activity and small explosions. At 2323 a pilot observed ash at an altitude of 3.7 km (12,000 ft) a.s.l. and a lava flow effusing from the intra-caldera cinder cone. Residents in Perryville (32 km SSE) and Port Moller (77 km WSW) also observed ash emissions at about 2330. During 15-18 June satellite images showed very high elevated surface temperatures at the intra-caldera cinder cone consistent with continued lava effusion. No plumes were observed in satellite images nor reported by pilots or local observers. Volcanic tremor continued to be detected.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


5 June-11 June 2013

On 8 June AVO reported that gradually increasing seismic tremor at Veniaminof had been detected during the previous two days. The Aviation Color Code was raised to Yellow and the Volcano Alert Level was raised to Advisory. Clear web-camera and satellite views showed nothing unusual at the volcano. During 8-10 June seismicity continued to increase and a persistent steam plume rose from the central cone within the caldera.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


20 May-26 May 2009

On 26 May, AVO reported that seismicity from Veniaminof had decreased during the previous week. The Volcanic Alert Level was lowered to Normal and the Aviation Color Code was lowered to Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


6 May-12 May 2009

During 6-7 May, seismic activity from Veniaminof increased, prompting AVO to raise the Volcanic Alert Level to Advisory and the Aviation Color Code to Yellow. Small magnitude earthquakes occurred at rates of 5-10 per hour during quieter periods and 1-3 per minute during periods of more intense activity. Visual observations indicated typical steaming from the summit caldera cone. Seismicity remained elevated during 8-12 May. Minor ash-producing explosions last occurred in March 2008.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


30 April-6 May 2008

AVO reported on 3 May that the Volcanic Alert Level for Veniaminof was lowered to Normal and the Aviation Color Code was lowered to Green due to the absence of ash emissions and elevated surface temperatures. Seismicity was still above past background levels, but the rate and intensity had declined over the previous several weeks.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


27 February-4 March 2008

AVO reported elevated seismic activity from Veniaminof during 27 February-4 March. Web camera views showed steaming from the cone and occasional small ash bursts that rose to 200 m above the crater on 27 February. During 28 February-3 March views were obscured by cloud cover; low-level steaming was seen on 29 February during a break in the weather.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


20 February-26 February 2008

AVO reported that on 22 February several minor ash bursts from Veniaminof were recorded by the seismic network and observed on web camera footage. The bursts rose to an altitude of below 2.7 km (9,000 ft) a.s.l. but fallout was confined to the crater. Sporadic increases in seismic activity were noted since 11 February, including tremor episodes that lasted 1-2 minutes and occurred several times per hour. The Aviation color code was raised to Yellow and the Alert Level was raised to Advisory. Steam plumes emitted from the intra-caldera cinder cone were seen on video footage during 23-25 February and seismic levels were elevated during 23-26 February.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


12 April-18 April 2006

During 7-14 April, seismicity at Veniaminof remained at low levels, but above background. Views of the volcano were obscured by clouds during the report period, and AVO received no information about ash clouds or activity at the volcano. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


5 April-11 April 2006

During 31 March to 7 April, low-altitude ash emissions occurred from Veniaminof and seismicity remained at low levels. On 6 April, a pilot reported an ash plume at a height of ~3 km (10,000 ft) a.s.l. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


22 March-28 March 2006

Web-camera images of Veniaminof on 24 March showed a steam-and-ash plume drifting from the summit cone at a height less than 2.3 km (7,600 ft) a.s.l. This level of activity was similar to activity on 23 March, but higher than activity on 21 and 22 March when a very diffuse steam-and-ash plume was confined to the summit caldera. The flow of seismic data from Veniaminof stopped on the evening of 21 March due to technical problems. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


8 March-14 March 2006

During 3-10 March, seismicity at Veniaminof was low but slightly above background. Clear web camera views on 9 March showed small diffuse ash plumes extending a short distance from the intracaldera cone. On 10 March, a pilot reported low-level ash emitted form the intracaldera cone. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


1 March-7 March 2006

The Concern Color Code at Veniaminof was increased from Green to Yellow on 3 March. That morning ash emissions rose a few hundred meters above the intracaldera cone, drifted E, and dissipated rapidly. Ashfall was expected to be minor and confined to the summit caldera. Seismicity was low and did not indicate that a significantly larger eruption was imminent. AVO expected that steam-and-ash emissions may continue intermittently for days to weeks and could pose a hazard to people and low-flying aircraft in the vicinity of the active cone.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


2 November-8 November 2005

The Concern Color Code at Veniaminof was increased on 4 November from Green to Yellow after a low-level minor ash emission occurred from the intracaldera cone beginning at 0929. Ash rose a few hundred meters above the cone, drifted E, and dissipated rapidly. Minor ashfall was probably confined to the summit caldera. During the previous 2 weeks, occasional steaming from the intracaldera cone was observed. Very weak seismic tremor and a few small discrete seismic events were recorded at the station closest to the active cone. However, AVO reported that there were no indications from seismic data that a significantly larger eruption was imminent. They expect that steam and ash emissions may continue intermittently and could pose a hazard to people and low-flying aircraft in the vicinity of the active cone.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


28 September-4 October 2005

AVO decreased the Concern Color Code at Veniaminof from Yellow to Green (the lowest level) on 28 September after seismicity at the volcano had been at background levels for over a week and there was no evidence to suggest that minor ash explosions were continuing.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


21 September-27 September 2005

Cloudy weather during 16-23 September prohibited web camera and satellite observations of Veniaminof, but seismic data indicated diminishing activity. Some minor ash emissions may have occurred, with diffuse ash plumes rising less than ~3 km (10,000 ft) a.s.l. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


14 September-20 September 2005

Based on interpretations of seismic data at Veniaminof, minor ash emission continued at a very low rate of 1-5 events per day. AVO reported that it was likely that diffuse ash plumes rose to heights less than ~3 km (10,000 ft) a.s.l. and were confined to the summit caldera. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


7 September-13 September 2005

On 7 September, AVO raised the Concern Color Code at Veniaminof from Green to Yellow after several minor bursts of ash occurred at the volcano during the afternoon. Ash bursts continued to occur through at least 9 September, with ash rising less than 3 km (10,000 ft) a.s.l. The ash was confined to the caldera. AVO reported that there were no indications that more vigorous activity was imminent or even likely. They expected that steam-and-ash emissions similar to those observed on 7 September might continue intermittently and could pose a hazard to people and low-flying aircraft in the vicinity of the active cone.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


2 March-8 March 2005

A reduction in activity at Veniaminof during 25 February to 4 March led AVO to reduce the Concern Color Code from Yellow to Green, the lowest level. For more than a week seismic activity was at background levels, periods of volcanic tremor had ceased, and there were no discrete events associated with ash bursts. Only minor emissions of steam were observed on the web camera and satellite imagery. AVO received no reports of ash emissions from pilots or observers on the ground. They concluded that given the decline in seismicity it appeared that the most recent episode of eruptive activity had ended at Veniaminof.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


23 February-1 March 2005

Seismic activity decreased substantially at Veniaminof during 18-25 February in comparison to previous weeks, leading AVO to decrease the Concern Color Code from Orange to Yellow. Periods of volcanic tremor diminished, and no discrete events associated with ash bursts had occurred for several days. Only minor steam emissions were seen. AVO received no reports of ash emissions from pilots or ground observers. AVO concluded that given the decline in seismicity, it appeared that the most recent episode of Strombolian eruptive activity at Veniaminof had ended.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


16 February-22 February 2005

During 11-18 February, it was likely that low-level Strombolian eruptive activity continued at Veniaminof based on seismic data and satellite imagery. Cloudy conditions obscured web camera views of the volcano, and no ash emissions were observed above the cloud cover. Seismicity remained above background levels at Veniaminof. The character of the seismicity changed slightly during the report period, with frequent periods of continuous banded volcanic tremor occurring, but the amplitudes of earthquakes did not increase. This activity was consistent with explosions from the active cone; however, there was no indication that these bursts are rose more than 4 km a.s.l. Veniaminof remained at Concern Color Code Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


9 February-15 February 2005

Low-level Strombolian eruptive activity continued at Veniaminof during 4-11 February. On 9 February, an ash burst rose hundreds of meters above the intracaldera cone. Satellite images continued to show a thermal anomaly in the vicinity of the intracaldera cone, consistent with the presence of hot material at the vent. Seismicity remained above background levels at the volcano. On the morning of 10 February there was a distinct increase in the amplitude and frequency of earthquakes. The increase continued through 11 February. This activity was consistent with more energetic explosions from the active cone, however there were no indications that the bursts rose higher than 4 km a.s.l. Veniaminof remained at Concern Color Code Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


2 February-8 February 2005

On the evening of 3 February, Strombolian activity at Veniaminof was visible by residents of Perryville ~30 km from the volcano. Activity was also observed on web camera views and seen by satellite as an increase in radiated surface heat. An increase in seismicity suggested that Strombolian activity may have continued through 4 February while the volcano was obscured by clouds.

During 28 January to 4 February, seismicity at Veniaminof was similar to levels for the previous week, with low-amplitude tremor and occasional larger bursts. During clear weather, satellite imagery showed anomalous heat at the summit cone, consistent with hot blocks and ash being ejected from the active vent. The web camera showed intermittent ash plumes reaching as high as 3 km a.s.l. Veniaminof remained at Concern Color Code Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


26 January-1 February 2005

During 21-28 January, seismic data, web camera views, and satellite images all indicated that low-level ash emissions at Veniaminof continued. Seismicity was similar to levels observed during the previous week, consisting of low-amplitude volcanic tremor with occasional larger bursts. During periods of clear weather, satellite imagery showed anomalous heat at the summit cone, consistent with hot blocks and ash being ejected from the active vent. The web camera showed intermittent ash plumes reaching as high as 3 km a.s.l. Occasional stronger bursts of seismic tremor around 28 January may have indicated plumes to higher levels, but not above 4 km a.s.l. Veniaminof remained at Concern Color Code Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


19 January-25 January 2005

During 14-21 January, seismic data, web camera views, and satellite images indicated that low-level ash emissions continued at Veniaminof. Seismicity was similar to levels observed during the previous week, consisting of low-amplitude volcanic tremor with occasional larger bursts. During clear weather, satellite imagery showed anomalous heat at the summit cone, consistent with hot blocks and ash being ejected from the active vent. In addition, the web camera showed intermittent ash plumes reaching as high as 3 km a.s.l. Occasional stronger bursts of seismic tremor during 20-21 January may have indicated plumes to higher levels, but not above 4 km. Veniaminof remained at Concern Color Code Orange.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


12 January-18 January 2005

On 12 January the Anchorage VAAC reported emission of a thin ash cloud, visible on the Perryville NetCam, that rose between 3-4 km a.s.l., extended ENE, and dissipated within ~55 km of the volcano.

On 14 January, a satellite image showed a thermal anomaly in the vicinity of the Veniaminof's summit. Although the anomaly appeared less intense than when first detected on 8 January and volcanic activity seemed to have declined significantly since 12 January, activity still remained significantly higher than normal with occasional bursts of volcanic tremor. Therefore, Veniaminof remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


5 January-11 January 2005

AVO raised the Concern Color Code at Veniaminof from Yellow to Orange on 10 January as ash emissions from the volcano's intracaldera cone reached heights of nearly 4 km during 8-10 January. Seismicity remained at elevated levels and satellite images showed a persistent thermal anomaly at the intracaldera cone. On 11 January, the Anchorage VAAC reported emission of a thin ash cloud to ~3 km a.s.l. visible on the Perryville NetCam

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


29 December-4 January 2005

AVO raised the Concern Color Code at Veniaminof from Green to Yellow on 4 January because around that time several small ash emissions from the volcano's intracaldera cone were observed on the Internet camera in Perryville. Ash emissions were visible starting around 0938, but may have been obscured by meteorological clouds in previous images. The discrete ash emissions were small, rose hundreds of meters above the cone, and dissipated as they drifted E. Minor ash fall was probably confined to the summit caldera. Very weak seismic tremor was recorded beginning on 1 January, and increased slightly over the next 2 days. These seismic signals were similar to those recorded during steam-and-ash emissions in April to October, 2004. However, there were no indications from seismic data that events significantly larger than those observed around 4 January are imminent. AVO expects that steam-and-ash emissions may continue intermittently and could pose a hazard to people and low-flying aircraft in the vicinity of the active cone.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


20 October-26 October 2004

AVO lowered the Concern Color Codeat Veniaminof on 26 October from Yellow to Green. Seismicity, which had been associated with ash emissions that occurred during the summer of 2004, decreased to levels that indicated ash, ash-and-steam, or steam emissions were no longer occurring on a regular basis. Since early September, no ash emissions were seen on the web camera and no evidence of ash was visible on satellite imagery. Also, AVO had received no recent reports of ash from pilots or ground observers. AVO considered the intermittent, low-level seismic tremor that continued to be recorded at the volcano to be part of the background activity. They reported that steaming from the intracaldera cone may still occur.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


13 October-19 October 2004

Low-level tremor continued at Veniaminof during 8-15 October, correlating with weak steaming of the intracaldera cone as observed on the web camera. No ash emissions were observed, although cloudy conditions over the caldera restricted viewing for much of the week. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


29 September-5 October 2004

During 24 September to 1 October, low-level tremor and intermittent small tremor bursts may have occurred at Veniominof, but high winds in the area made analysis of seismic records inconclusive. The winds were strong enough to produce an overshadowing effect on seismic records that could hide evidence of low-level tremor. If the tremor episodes continued, they likely represented low-level ash-and-steam emissions similar to those observed over the previous 4 months. Cloudy conditions obscured views of the volcano in web camera and satellite data. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


22 September-28 September 2004

Low-level tremor and intermittent tremor bursts continued at Veniaminof during 17-24 September. Tremor episodes likely represented low-level ash-and-steam emissions similar to those observed over the previous 4 months, although cloudy conditions obscured views of the volcano in web camera and satellite imagery. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


15 September-21 September 2004

Low-level seismic tremor and intermittent tremor bursts continue to be recorded at Veniaminof. Tremor episodes likely represent low-level ash and steam emissions similar to those observed over the past four months. Minor emissions of volcanic ash and steam were occasionally observed using web camera images during times of clear weather. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


8 September-14 September 2004

Both low-level tremor and intermittent bursts of tremor continued at Veniaminof during 3-10 September. AVO scientists believed these tremor episodes likely represented low-level ash-and-steam emissions similar to those observed during the previous 4 months. Minor emissions of ash and steam were occasionally seen on the web camera during clear weather. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


1 September-7 September 2004

Both low-level tremor and intermittent bursts of tremor continued at Veniaminof during 27 August to 3 September. AVO scientists believed tremor episodes likely represented low-level ash-and-steam emissions similar to those observed during the previous 2 months. Minor emissions of ash and steam were occasionally seen on the web camera during clear weather. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


25 August-31 August 2004

During 20-27 August, low-level seismic tremor and intermittent tremor bursts continued at Veniaminof. Inclement weather prohibited direct observations and satellite views. AVO scientists believed tremor episodes likely represented low-level ash-and-steam emissions similar to those observed during the previous 2 months. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


18 August-24 August 2004

Episodes of volcanic tremor continued intermittently at Veniaminof during 13-20 August. Occasional small ash-and-steam emissions occurred during the report week that were similar to those observed over the previous 2 months. None rose above 3 km a.s.l. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


11 August-17 August 2004

During 6-13 August, frequent small ash-and-steam emissions from Veniaminof were visible on the web camera in Perryville and confirmed by AVO geologists working in the area. The emissions did not exceed a height of 3 km a.s.l. and were similar to those commonly observed in the past 2 months. Bursts of volcanic tremor recorded intermittently on 17 August were probably associated with low-level, short-term ash emissions. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


4 August-10 August 2004

Episodes of volcanic tremor continued intermittently at Veniaminof from 30 July to 6 August. No visual observations of ash emissions had been made since 22 July, although the recorded seismicity was similar to that observed during ash emissions in the previous weeks. During the report period, occasional low-level steam plumes were seen on the AVO web camera. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


28 July-3 August 2004

Episodes of volcanic tremor continued intermittently at Veniaminof during 22-30 July. No visual observations of ash emissions were made after 22 July, although the recorded seismicity was similar to that observed during ash emissions in the previous few months. Most such emissions did not reach 3 km a.s.l., though a few reportedly reached as high as 3.7 km. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


21 July-27 July 2004

Small steam-and-ash emissions were accompanied by periods of volcanic tremor at Veniaminof during 16-23 July. On 22 July at 1229, an AVO field crew witnessed a small ash burst rise a few hundred meters above the summit of the intracaldera cone. This type of activity prevailed at Veniaminof during the previous 3 months. During periods of repose in the report week, the cone produced variable amounts of white steam from at least two separate craters near its top. The snow-and-ice field over much of the caldera was covered with a discontinuous, 1- to 2-mm thick ash blanket. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


14 July-20 July 2004

Short intervals of low-level volcanic tremor continued intermittently at Veniaminof during 9-16 July. According to AVO, the episodes of tremor correlated well with small ash-and-steam emissions that may have reached as high as 3.6 km a.s.l. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


7 July-13 July 2004

Many episodes of short-lived bursts of volcanic tremor continued at Veniaminof during 7-13 July. AVO reported that the tremor correlated well with ash-and-steam plumes as high as 1.5 km a.s.l. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


30 June-6 July 2004

Short intervals of volcanic tremor occurred at Veniaminof during 25 June to 2 July. AVO reported that the tremor could be indicative of small, low-level ash-and-steam emissions. Small amounts of dark ash were seen in the ice-filled caldera on 27 June. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


16 June-22 June 2004

During 11-18 June, bursts of volcanic tremor continued intermittently at Veniaminof that may have been indicative of small, low-level ash emissions. On 16 June at 2350, a pilot observed an ash cloud that rose to a height of ~2.7 km a.s.l. The plume was also visible on satellite imagery. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


9 June-15 June 2004

Bursts of volcanic tremor continued at Veniaminof during 4-11 June. The only significant ash emissions occurred during the evening of 30-31 May. No emission exceeded 3 km a.s.l. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


26 May-1 June 2004

During 21-28 May, the level of volcanic activity at Veniaminof was generally lower than during the previous week. Sequences of tremor accompanying ash bursts continued. On video, weak steaming and low ash bursts were seen emanating from the intracaldera cone. Most of the ash bursts did not rise above the active cone (2,156 m). Satellite imagery on 26 May showed ash deposits on the N and SE portions of the caldera. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


19 May-25 May 2004

Unrest continued at Veniaminof during 14-21 May, characterized by intermittent volcanic tremor. The tremor was similar to seismic signals recorded the previous month in association with small ash plumes, suggesting that ash bursts continued. A pilot report on 18 May indicated the presence of an ash plume rising to heights of 300-900 m above the volcano's summit and extending ~32 km NE. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


12 May-18 May 2004

During 7-14 May unrest continued at Veniaminof, characterized by intermittent low-level volcanic tremor and small volcanic earthquakes. No emissions were seen. In comparison to the previous week, seismicity was more intermittent and lower in amplitude. However, seismicity suggested that ash bursts occasionally occurred. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


5 May-11 May 2004

Unrest continued at Veniaminof during 30 April to 7 May, characterized by small intermittent ash emissions, low-level volcanic tremor, and small volcanic earthquakes. Small ash emissions were observed during periods of clear weather during 1-3 May, rising to 2.4-2.8 km a.s.l. Seismicity was at levels similar to the previous week, suggesting that ash-burst activity continued. Satellite imagery showed ash deposits on the volcano's snow-covered flanks as far as ~8 km from the vent. A pilot reported seeing ash as far as 33 km from the cone. Veniaminof remained at Concern Color Code Yellow.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


28 April-4 May 2004

Unrest at Veniaminof during 23-30 April was characterized by small intermittent ash emissions, low-level volcanic tremor, and small volcanic earthquakes. Small ash emissions were observed during clear weather on 25 and 28 April rising to ~1 km above the active cone. Seismic activity fluctuated, but remained above background levels. There were no indications that more vigorous activity was imminent. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


21 April-27 April 2004

After a period of heightened seismicity at Veniaminof during 14-17 April that led AVO to increase the Concern Color Code from Green to Yellow, there was a marked decrease in the episodes of low-level volcanic tremor and small volcanic earthquakes through 26 April. A newly installed internet-based video camera located in Perryville allowed AVO to observe the volcano during clear weather. During the afternoon and evening of 25 April, more than 25 small steam-and-ash emissions were seen during an 8-hour period, producing clouds that rose 300-600 m above the active cone. These clouds typically were confined to the summit caldera, but could pose a hazard to people and low-flying aircraft in the immediate vicinity of the active cone. Through 26 April, Veniaminof remained at Concern Color Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


14 April-20 April 2004

During 10-17 April, Veniaminof showed heightened seismicity with several episodes of volcanic tremor and earthquakes. Seismicity decreased significantly prior to the emission of a gas plume with some ash throughout 18 April. The most vigorous phase occurred at about 1730 on 18 April when the plume rose to ~0.5 km above the crater. At about 1130 on 19 April another period of heightened seismic activity began. Due to the increased activity, Veniaminof was upgraded to Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


25 February-2 March 2004

Following reports of low-level steam-and-ash emissions from Veniaminof during the week of 15 February, satellite imagery on 22 February showed very localized ash deposits within the ice-filled caldera. No additional signs of volcanic activity were visible on satellite imagery during 23-27 February, and there were no more reports of ash-plume sightings from Perryville. Seismicity remained at low levels, and the thermal signature of the intracaldera cone was unchanged from previous months. AVO determined that the small ash bursts were most likely the result of minor explosions caused by the heating of ground water below the intracaldera cone. Veniaminof remained at Concern Color Code Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


18 February-24 February 2004

During the week of 15 February, AVO received several reports of small ash clouds rising "several hundred feet" above the intracaldera cinder-and-spatter cone of Veniaminof. Residents of Perryville reported a "black puff" of ash on 16 February followed by strong steaming, and a pilot reported a small black ash cloud on 19 February. Satellite imagery on 19 February at 1410 showed a small, dark trail on the snow leading away from the intracaldera cone that was likely a very localized ash deposit. No significant seismic activity or thermal anomalies on satellite data were recorded during the week. Due to the lack of significant seismic activity beneath the volcano, AVO concluded that these small ash clouds were the result of minor explosions caused by the heating of ground water below the intracaldera cone. Veniaminof remained at Concern Color Code Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


9 April-15 April 2003

Seismic activity remained at very low levels at Veniaminof during 4-11 April. Tremor was almost completely absent, and only a few low-frequency events were recorded. Satellite images during the week did not reveal any elevated surface temperatures, ash emissions, or ash deposits at the volcano. Due to the decline in seismicity, AVO lowered the Concern Color Code for Veniaminof from Yellow to Green. AVO stated that while Veniaminof is in its current state of activity, low-level steaming and minor ash emissions may periodically occur.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


2 April-8 April 2003

Seismicity dramatically decreased at Veniaminof during 28 March to 4 April. However, short periods of volcanic tremor and low-frequency events continued to occur. AVO reported that low-level steaming and minor ash emissions might occur at any time. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


26 March-1 April 2003

The elevated seismicity that began in mid-December 2002 at Veniaminof continued during 21-28 March, but declined in comparison to previous weeks. Seismicity was characterized by very low amplitude tremor. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


12 March-18 March 2003

The elevated seismicity that began in mid-December 2002 at Veniaminof continued during 7-14 March. On 11 March a 4-hour period of continuous seismic tremor was recorded, followed by 17 hours of discrete seismic events and 3- to 4-minute-long tremor bursts. This culminated with another 4-hour period of continuous tremor on 12 March. Seismicity then declined, and by the 14th was characterized by the occurrence of about one small-amplitude discrete seismic event every 1-2 minutes. AVO reported that based on this seismicity, low-level steaming and minor ash-emissions may occur at any time. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


12 February-18 February 2003

The elevated seismicity that began at Veniaminof in mid-December 2002 continued through 7-14 February. Discrete seismic events occurred at rates up to 1 event per minute. AVO stated that at this level of seismic unrest, low-level steaming, and minor ash emissions may occur at any time. No elevated surface temperatures, ash emissions, or ash deposits were noted on satellite images. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


5 February-11 February 2003

The elevated seismicity that began at Veniaminof in mid-December 2002 continued through 31 January to 7 February. Discrete seismic events occurred at rates up to 1 event per minute. AVO stated that at this level of seismic unrest, low-level steaming and minor ash emissions may occur at any time. No elevated surface temperatures, ash emissions, or ash deposits were noted on satellite images. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


29 January-4 February 2003

The elevated seismicity that began at Veniaminof in mid-December 2002 continued through 24-31 January. Discrete seismic events occurred at rates up to 1-2 events per minute, although event rates and peak amplitudes decreased somewhat over the last 2 days. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


22 January-28 January 2003

The elevated seismicity that began in mid-December 2002 at Veniaminof continued during 17-24 January. As during the previous week, periods of nearly constant seismicity were recorded during the report week. Discrete seismic events occurred at rates up to 1-2 events per minute, along with moderate levels of volcanic tremor. Satellite imagery did not reveal increased surface temperatures, ash emission, or ash deposits. Visual observations on 22 January from the village of Perryville, located 35 km SSW of the volcano, revealed that white steam was rising from the intracaldera cone. The steaming was similar to that observed over the previous several months. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


15 January-21 January 2003

The elevated seismicity that began in mid-December 2002 at Veniaminof continued during 10-17 January. As during the previous week, periods of nearly constant seismicity were recorded during the report week. Discrete seismic events occurred at rates up to 1-2 events per minute, along with moderate levels of volcanic tremor. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


8 January-14 January 2003

The elevated seismicity that began in mid-December 2002 at Veniaminof continued during 3-10 January. Nearly constant periods of seismicity were recorded during the report week. Discrete seismic events occurred at rates up to 1-2 events per minute, along with moderate levels of volcanic tremor. The Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


31 December-6 January 2003

Periods of nearly constant seismicity at Veniaminof since 31 December led AVO to raise the Concern Color Code from Green to Yellow on 6 January. Seismicity had been increasing since mid-December. No thermal anomalies were detected on satellite imagery. AVO stated that there were no indications of an imminent eruption, although low-level steaming and minor ash emission may occur.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


13 November-19 November 2002

On 18 November AVO lowered the Concern Color Code at Veniaminof from Yellow to Green. Since early October they had received no pilot reports or other observations of activity at the volcano. Also, they had not detected thermal anomalies in any clear satellite images. Though seismicity remained above levels recorded this summer, it has remained roughly constant for the past month at a level notably lower than in September, when the color code was raised to Yellow. AVO stated that while Veniaminof is in its current state of activity, low-level steaming and minor ash emissions may periodically occur.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


30 October-5 November 2002

Veniaminof remained restless during 25 October to 1 November. Although the current seismic activity is lower than when first noted in early September, it is still above background level. AVO received video footage recorded in early October that showed minor ash emission from the intracaldera cone. The ash rose about 100-200 m above the cone and drifted a short distance before dispersing. A faint covering of ash was visible on the caldera ice field extending from the base of the cone. These observations are consistent with the elevated level of seismicity and are indicative of the type of minor activity that is occurring. Due to the continuing seismicity and reports of minor ash emissions the Concern Color Code at Veniaminof remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


23 October-29 October 2002

Veniaminof remained restless during 18-25 October. Although the current seismic activity is lower than when first noted in early September, it is still above background level. No new visual observations of Veniaminof were received since the last update. No thermal anomalies were observed in satellite views. AVO considered the activity at Veniaminof to be minor, but the exact nature of the unrest was unknown. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


16 October-22 October 2002

Veniaminof remained restless during 11-18 October. Although seismicity was lower than when first noted in early September, it was still above background levels. No new visual observations had been received since the last update. However, local observations of low-level activity earlier in the month confirm that small explosions at the intracaldera cone are possible at any time and may not correspond with a noticeably elevated level of seismicity. No thermal anomalies were observed on satellite imagery. AVO considered the activity at Veniaminof to be minor, but the exact nature of the unrest was unknown. Veniaminof remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


9 October-15 October 2002

Veniaminof remained restless during 4-11 October. Although seismicity was lower than when first noted in early September, it was still above background levels. Visual observations of Veniaminof during the week were intermittent and inconclusive. No thermal anomalies were observed on satellite imagery. AVO considered the activity at Veniaminof to be minor, but the exact nature of the unrest remained unknown. The Level of Concern Color Code remained Yellow due to the continuing seismicity.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


2 October-8 October 2002

Veniaminof remained restless during 26 September to 4 October. Seismicity was lower than when it was first noted in early September, although it was still above background level. Visual observations of Veniaminof were intermittent and inconclusive. AVO received reports ranging from minor-steam and possible ash emissions, to no signs of activity. A satellite image recorded on 2 October suggested an apparent gray, diffuse deposit extending across the caldera from the historically active intracaldera cinder cone. This could reflect a small explosion, vigorous steam emission, or redistribution of material on the cone by strong winds. No thermal anomalies were observed on satellite imagery. AVO considered the activity at Veniaminof to be minor, but the exact nature of the unrest remained unknown. Due to the continuing seismicity and reports of unusual steaming, the Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


25 September-1 October 2002

AVO reported that seismic unrest that began at Veniaminof on 10 September continued through the 27th. The intensity of tremor and small earthquakes under the volcano had decreased since the 10th, but remained above the background level established during the summer of 2002. Visual observations of Veniaminof were hampered by poor weather. On 24 September, residents of Perryville, 35 km S of the volcano, reported and photographed small bursts of steam, possibly containing minor amounts of ash, rising just above the historically active intracaldera cinder cone. Without additional observations, AVO could not determine if this indicated very low-level eruptive activity or vigorous steaming from the cone. On several occasions of relatively clear weather conditions, AVO observed no signs of elevated temperature or ash emission on satellite imagery. Due to the continuing seismicity and reports of unusual steaming, the Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


18 September-24 September 2002

Pulses of low-frequency tremor were first recorded on 10 September by several seismic stations at Veniaminof. Until at least 20 September the overall level of seismicity decreased, but remained above background. AVO did not receive any reports of anomalous activity, and poor weather limited satellite observations. Due to the anomalous seismicity, the Concern Color Code remained at Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


11 September-17 September 2002

On 10 September AVO detected 1-minute-long pulses of low-frequency tremor occurring every 2-5 minutes on several seismic stations at Veniaminof. This type of seismicity is indicative of volcanic unrest. Retrospective analysis of seismic data suggested that tremor began as early as 8 September. Through at least 16 September the overall level of seismicity decreased, but remained above background levels. Veniaminof was at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
2013 Jun 13 2013 Sep 16 (?) Confirmed 3 Historical Observations Western intracaldera cone
2008 Feb 22 2008 Feb 27 (?) Confirmed 1 Historical Observations Western intracaldera cone
2006 Mar 3 2006 Sep 7 Confirmed 1 Historical Observations Western intracaldera cone
2005 Sep 7 2005 Nov 4 (?) Confirmed 1 Historical Observations Western intracaldera cone
2005 Jan 4 2005 Feb 14 ± 3 days Confirmed 2 Historical Observations Western intracaldera cone
2004 Feb 16 2004 Sep 5 ± 4 days Confirmed 2 Historical Observations Western intracaldera cone
2002 Sep 24 2003 Mar 23 Confirmed 1 Historical Observations Western intracaldera cone
1995 Nov 15 1995 Nov 30 (?) Confirmed 1 Historical Observations Western intracaldera cone
1995 Apr 17 1995 Apr 17 Confirmed 1 Historical Observations Western intracaldera cone
1993 Jul 30 1994 Sep 28 (?) Confirmed 2 Historical Observations Western cone and Half Cone
1987 Mar 19 1987 Mar 19 Confirmed 1 Historical Observations Western intracaldera cone
1984 Nov 29 1984 Dec 6 (?) Confirmed 2 Historical Observations Western intracaldera cone
1983 Jun 2 1984 Apr 17 Confirmed 3 Historical Observations Western intracaldera cone
1956 Mar 1956 May 23 Confirmed 3 Historical Observations Western intracaldera cone
1944 Mar 28 Unknown Confirmed 2 Historical Observations Western intracaldera cone
1939 Nov Unknown Confirmed 2 Historical Observations Western intracaldera cone
1939 May 23 1939 Jun 26 (?) Confirmed 3 Historical Observations Western intracaldera cone
1930 Jun Unknown Confirmed 2 Historical Observations Western intracaldera cone
1892 Aug 28 1892 Aug 30 Confirmed 3 Historical Observations Western intracaldera cone
1874 Jul 15 ± 45 days Unknown Confirmed 2 Historical Observations Western intracaldera cone
[ 1852 ] [ Unknown ] Uncertain 2   Western intracaldera cone
1838 Aug 4 1839 Apr Confirmed 3 Historical Observations Western intracaldera cone
[ 1830 ] [ 1838 ] Uncertain 2  
1750 BCE (?) Unknown Confirmed 6 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.

Burk C A, 1965. Geology of the Alaska Peninsula-island arc and continental margin (Part 1). Geol Soc Amer Mem, 99: 1-250.

Coats R R, 1950. Volcanic activity in the Aleutian Arc. U S Geol Surv Bull, 974-B: 35-47.

Henning R A, Rosenthal C H, Olds B, Reading E (eds), 1976. Alaska's volcanoes, northern link in the ring of fire. Alaska Geog, 4: 1-88.

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior..

Miller T P, McGimsey R G, Richter D H, Riehle J R, Nye C J, Yount M E, Dumoulin J A, 1998. Catalogue of the historically active volcanoes of Alaska. U S Geol Surv Open-File Rpt, 98-582: 1-104.

Miller T P, Smith R L, 1977. Spectacular mobility of ash flows around Aniakchak and Fisher Calderas, Alaska. Geology, 5: 173-176.

Motyka R J, Liss S A, Nye C J, Moorman M A, 1993. Geothermal resources of the Aleutian arc. Alaska Div Geol Geophys Surv, Prof Rpt, no 114, 17 p and 4 map sheets.

Smith R L, Shaw H R, Luedke R G, Russell S L, 1978. Comprehensive tables giving physical data and thermal energy estimates for young igneous systems of the United States. U S Geol Surv Open-File Rpt, 78-925: 1-25.

Wood C A, Kienle J (eds), 1990. Volcanoes of North America. Cambridge, England: Cambridge Univ Press, 354 p.

Massive Veniaminof volcano, one of the highest and largest volcanoes on the Alaska Peninsula, is truncated by a steep-walled, 8 x 11 km, glacier-filled caldera that formed around 3700 years ago. The caldera rim is up to 520 m high on the north, is deeply notched on the west by Cone Glacier, and is covered by an ice sheet on the south. Post-caldera vents are located along a NW-SE zone bisecting the caldera that extends 55 km from near the Bering Sea coast, across the caldera, and down the Pacific flank. Historical eruptions probably all originated from the westernmost and most prominent of two intra-caldera cones, which reaches an elevation of 2156 m and rises about 300 m above the surrounding icefield. The other cone is larger, and has a summit crater or caldera that may reach 2.5 km in diameter, but is more subdued and barely rises above the glacier surface.