San Miguel

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  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 13.434°N
  • 88.269°W

  • 2130 m
    6986 ft

  • 343100
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

9 April-15 April 2014

According to SNET, the Ministerio de Medio Ambiente y Recursos Naturales (MARN) reported that on 12 April moderate to strong gas plumes from San Miguel rose from the crater and drifted SW. The most robust plume occurred at 1607 and rose 400 m. Images recorded by a webcam showed that the plumes had dark tones, suggesting small amounts of ash.

Source: Servicio Nacional de Estudios Territoriales (SNET)



 Available Weekly Reports


2014: January | April
2013: December
2011: March
2010: August
2009: July
2006: October
2005: October
2004: February
2002: October


9 April-15 April 2014

According to SNET, the Ministerio de Medio Ambiente y Recursos Naturales (MARN) reported that on 12 April moderate to strong gas plumes from San Miguel rose from the crater and drifted SW. The most robust plume occurred at 1607 and rose 400 m. Images recorded by a webcam showed that the plumes had dark tones, suggesting small amounts of ash.

Source: Servicio Nacional de Estudios Territoriales (SNET)


15 January-21 January 2014

SNET reported that during 15-20 January RSAM values at San Miguel fluctuated between 14 and 97, except for a period starting at 1500 on 19 January where the values were 102-215. Gas emissions were characterized by light gray plumes that rose 100-250 m above the crater and drifted S and SW.

Source: Servicio Nacional de Estudios Territoriales (SNET)


8 January-14 January 2014

SNET reported that during 8-10 January activity at San Miguel was low. The number of seismic events fluctuated but remained at low levels, sometimes lower than values recorded before the eruption on 29 December 2013. Gas emissions were also low and characterized by light gray plumes that rose 100-150 m above the crater and drifted S. RSAM values and sulfur dioxide emissions increased for a period of time during 11-12 January, but decreased again to low levels.

Source: Servicio Nacional de Estudios Territoriales (SNET)


1 January-7 January 2014

SNET reported that sulfur dioxide gas flux in tonnes per day from San Miguel was high: 2,200 on 31 December 2013, 1,740 on 1 January 2014, and 700 on 2 January. The report noted that the measurement on 2 January was likely low due to changes in wind patterns that day. During 1-2 January RSAM values ranged from 17 to 28 units. On 5 January gas plumes rose as high as 150 m above the crater. The next day light-gray gas plumes rose 200 m and drifted SW. RSAM values during 5-6 January were between 15 and 33 units.

Source: Servicio Nacional de Estudios Territoriales (SNET)


25 December-31 December 2013

According to news articles, an explosive eruption at San Miguel that began at 1030 on 29 December prompted an evacuation of 1,400-2,600 people. A dense ash plume rose from the crater. Based on wind data, the Washington VAAC reported that the ash plume rose to an altitude of 9.7 km (32,000 ft) a.s.l. and drifted ENE at higher altitudes and W at lower altitudes.

SNET reported that sulfur dioxide flux was 637 tonnes per day on 29 December and 1,244 tonnes per day on 30 December. During 30-31 December seismicity decreased significantly. Through the morning of 31 December emissions had consisted of gas and slight amounts of ash that drifted WSW.

Sources: Servicio Nacional de Estudios Territoriales (SNET), Washington Volcanic Ash Advisory Center (VAAC), United Press International (UPI), elsalvador.com


23 March-29 March 2011

Servicio Nacional de Estudios Territoriales (SNET) reported that during a survey of the San Miguel crater on 9 and 16 March observers noted pulses of gas rising 200 m from the crater. On 12 March the number and amplitude of earthquakes increased. RSAM values rose the next day to 121 units per day on average, up from normal values around 50 units per day. RSAM values continued to fluctuate during the next few days and reached as high as 319 units on 19 March, 414 units on 20 March, and 234 on 21 March. On 18 and 20 March, local residents felt vibrations and heard minor rumbling. Observations on 25 March indicated that gas plumes rose 100 m from the crater. On 28 March SNET noted that seismicity had gradually decreased during the previous few days, and was as low as 80 RSAM units on 27 March. Access to areas within a 2-km-radius remained restricted.

Source: Servicio Nacional de Estudios Territoriales (SNET)


11 August-17 August 2010

On 13 August, Servicio Nacional de Estudios Territoriales (SNET) reported that seismicity remained above background levels after an increase was detected on 1 August. Average background RSAM values ranged from 15 to 50 units per day. During 12-13 August, RSAM values ranged between 433 and 465. Over the next few days, seismicity decreased significantly; from 14 August to 16 August, RSAM values decreased from 188 to 132. Access to areas within a 2-km-radius remained restricted.

Source: Servicio Nacional de Estudios Territoriales (SNET)


15 July-21 July 2009

On 20 July, Servicio Nacional de Estudios Territoriales (SNET) reported that the amplitude of seismic events from San Miguel had decreased to normal or background levels. Access to areas within a 2-km-radius continued to be restricted.

Source: Servicio Nacional de Estudios Territoriales (SNET)


8 July-14 July 2009

Servicio Nacional de Estudios Territoriales (SNET) reported that the amplitude of seismic events from San Miguel had decreased during 9-13 July, but RSAM values remained above the background average. Access to areas within a 2-km-radius was restricted.

Source: Servicio Nacional de Estudios Territoriales (SNET)


1 July-7 July 2009

Servicio Nacional de Estudios Territoriales (SNET) reported that seismic amplitude from San Miguel increased for a period of time between 0500 and 1400 on 6 July. Seismicity remained elevated above background levels on 7 July.

Source: Servicio Nacional de Estudios Territoriales (SNET)


11 October-17 October 2006

Servicio Nacional de Estudios Territoriales (SNET) reported on 10 October that an Alert Level for San Miguel was established as Green within 4 km from the center of the crater due to a slight increase in seismic activity. On 15 October, the Alert Level was increased to Yellow due to further increases in seismic activity, but then decreased to Green again the next day.

Source: Servicio Nacional de Estudios Territoriales (SNET)


12 October-18 October 2005

SNET reported that activity had not changed at San Miguel after small clusters of earthquakes occurred at the volcano during 27 September to about 14 October. During a visit to the volcano on 13 October small rockfalls were seen, but there were no significant changes in the crater and sulfur-dioxide emissions were very weak.

Source: Servicio Nacional de Estudios Territoriales (SNET)


11 February-17 February 2004

According to a news article, a tectonic earthquake near San Miguel on the evening of 8 February caused landslides within the crater and on the volcano's flanks. One of the landslides threatened retention walls in the community of Carretos near the volcano. Citizens feared that heavy rains in the future could mix with the landslide material and overload the retention walls, causing them to fail.

Source: La Prensa Grafica


30 October-5 November 2002

A news report stating that a rockslide released dangerous fumes at San Miguel on 17 October was found to be false.

Source: Associated Press


23 October-29 October 2002

A news report stating that a rockslide released dangerous fumes at San Miguel on 17 October was found to be false.

Source: Associated Press


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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
2002 Jan 16 2002 Jan 16 Confirmed 1 Historical Observations
1997 Dec 31 Unknown Confirmed 1 Historical Observations
1995 Jan 12 1995 Apr 19 Confirmed 1 Historical Observations
1985 Nov 1986 Feb (in or after) Confirmed 1 Historical Observations
1976 Dec 2 1977 Mar 1 Confirmed 1 Historical Observations
1970 Mar 30 1970 Apr 5 Confirmed 1 Historical Observations
1967 Jan 5 Unknown Confirmed 2 Historical Observations
1966 Jul Unknown Confirmed 2 Historical Observations
1966 Feb 22 Unknown Confirmed 2 Historical Observations
1964 Oct 23 1964 Nov Confirmed 2 Historical Observations
1954 Oct 21 1954 Oct 21 Confirmed 2 Historical Observations
1939 May 1939 Jul Confirmed 2 Historical Observations
[ 1936 (?) ] [ Unknown ] Uncertain 2  
1931 Mar 1931 Jun Confirmed 2 Historical Observations
1930 Jan 26 ± 5 days Unknown Confirmed 2 Historical Observations
1929 Aug Unknown Confirmed 2 Historical Observations
1920 Aug 14 1925 Confirmed 2 Historical Observations
1919 Dec 10 1920 Jan Confirmed 2 Historical Observations
1890 1891 Confirmed 2 Historical Observations
1884 Jan 25 1884 Jan 28 ± 1 days Confirmed 2 Historical Observations NE side of main crater
1882 Dec 5 ± 4 days Unknown Confirmed 2 Historical Observations
1867 Dec 14 1868 Feb 16 (in or after) Confirmed 2 Historical Observations WSW flank (1000 m)
1862 Jan Unknown Confirmed 2 Historical Observations
1857 Nov Unknown Confirmed 2 Historical Observations
1855 Dec Unknown Confirmed 2 Historical Observations SSE flank (800 m)
[ 1854 ] [ Unknown ] Uncertain 2  
1844 Jul 25 1848 Confirmed 2 Historical Observations NNW (1120 m) and upper east flanks
1819 Jul 18 Unknown Confirmed 2 Historical Observations SSE flank (400 m; near Los Perolitos)
[ 1811 ] [ Unknown ] Uncertain 2  
[ 1798 (?) ] [ Unknown ] Uncertain 2  
1787 Sep 21 1787 Sep 23 Confirmed 2 Historical Observations Summit, north and SE flanks
1769 Unknown Confirmed 2 Historical Observations East flank ?
1762 Unknown Confirmed 2 Historical Observations NE flank (400 m)
1699 Unknown Confirmed 2 Historical Observations SE flank (400 m)
1510 ± 5 years Unknown Confirmed   Historical Observations

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.

Carr M J, 1984. Symmetrical and segmented variation of physical and geochemical characterisitics of the Central American volcanic front. J Volc Geotherm Res, 20: 231-252.

Chesner C A, Pullinger C R, Escobar C D, 2004. Physical and chemical evolution of San Miguel volcano, El Salvador. In: Rose W I, Bommer J J, Lopez D L, Carr M J, Major J J (eds), Natural Hazards in El Salvador, {Geol Soc Amer Spec Pap}, 375: 213-226.

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

Major J J, Schilling S P, Pullinger C R, Escobar C D, 2004. Debris-flow hazards at San Salvador, San Vicente, and San Miguel volcanoes, El Salvador. In: Rose W I, Bommer J J, Lopez D L, Carr M J, Major J J (eds), Natural Hazards in El Salvador, {Geol Soc Amer Spec Pap}, 375: 89-108.

Major J J, Schilling S P, Pullinger C R, Escobar C D, Chesner C A, Howell M M, 2001. Lahar-hazard zonation for San Miguel volcano, El Salvador. U S Geol Surv Open-File Rpt, 01-395: 1-14.

Mooser F, Meyer-Abich H, McBirney A R, 1958. Central America. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 6: 1-146.

Rodriquez L A, Watson M W, Rose W I, Branan Y K, Bluth G J S, Chigna G, Matias O, Escobar D, Carn S A, Fischer T P, 2004. SO2 emissions to the atmosphere from active volcanoes in Guatemala and El Salvador, 1999-2002. J Volc Geotherm Res, 138: 325-344.

Sapper K, 1925. The Volcanoes of Central America. Halle: Verlag Max Niemeyer, 144 p.

Weber H S, Wiesemann G, 1978. Mapa Geologico de la Republica de El Salvador/America Central. Bundesanstalt fur Geowissenschaften und Rohstoffe, Hannover, Germany, 1:100,000 scale geologic map in 6 sheets.

Williams H, Meyer-Abich H, 1955. Volcanism in the southern part of El Salvador with particular reference to the collapse basins of Lakes Coatepeque and Ilopango. Univ Calif Pub Geol Sci, 32: 1-64.

The symmetrical cone of San Miguel volcano, one of the most active in El Salvador, rises from near sea level to form one of the country's most prominent landmarks. The unvegetated summit of the 2130-m-high volcano rises above slopes draped with coffee plantations. A broad, deep crater complex that has been frequently modified by historical eruptions (recorded since the early 16th century) caps the truncated summit of the towering volcano, which is also known locally as Chaparrastique. Radial fissures on the flanks of the basaltic-andesitic volcano have fed a series of historical lava flows, including several erupted during the 17th-19th centuries that reached beyond the base of the volcano on the north, NE, and SE sides. The SE-flank lava flows are the largest and form broad, sparsely vegetated lava fields crossed by highways and a railroad skirting the base of the volcano. The location of flank vents has migrated higher on the edifice during historical time, and the most recent activity has consisted of minor ash eruptions from the summit crater.