Report on San Miguel (El Salvador) — 12 October-18 October 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
12 October-18 October 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on San Miguel (El Salvador). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 12 October-18 October 2005. Smithsonian Institution and US Geological Survey.
13.434°N, 88.269°W; summit elev. 2130 m
All times are local (unless otherwise noted)
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.
Geological Summary. The symmetrical cone of San Miguel, one of the most active volcanoes in El Salvador, rises from near sea level to form one of the country's most prominent landmarks. A broad, deep, crater complex that has been frequently modified by eruptions recorded since the early 16th century caps the truncated unvegetated summit, also known locally as Chaparrastique. Flanks eruptions of the basaltic-andesitic volcano have produced many lava flows, including several during the 17th-19th centuries that extended to the N, NE, and SE. The SE-flank flows are the largest and form broad, sparsely vegetated lava fields crossed by highways and a railroad skirting the base of the volcano. Flank vent locations have migrated higher on the edifice during historical time, and the most recent activity has consisted of minor ash eruptions from the summit crater.