Report on Soputan (Indonesia) — 15 October-21 October 2008
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
15 October-21 October 2008
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2008. Report on Soputan (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 15 October-21 October 2008. Smithsonian Institution and US Geological Survey.
1.112°N, 124.737°E; summit elev. 1785 m
All times are local (unless otherwise noted)
CVGHM reported that the Alert Level for Soputan was lowered from 3 to 2 (on a scale of 1-4) on 21 October. CVGHM reported additional information describing the eruption that prompted the Alert Level increase on 6 October. Gray plumes rose to an altitude of 2.8 km (9,200 ft) a.s.l. and were accompanied by Strombolian activity that ejected incandescent material 50-150 m above the crater. On 7 October, white plumes rose to altitudes of 2.3-3.3 km (7,500-10,800 ft) a.s.l. Incandescent material was again ejected 50-150 m from the crater. Incandescent rockfalls traveled 500 m W. The next day, plumes rose to an altitude of 2 km (6,600 ft) a.s.l.
Geological Summary. The Soputan stratovolcano on the southern rim of the Quaternary Tondano caldera on the northern arm of Sulawesi Island is one of Sulawesi's most active volcanoes. The youthful, largely unvegetated volcano is the only active cone in the Sempu-Soputan volcanic complex, which includes the Soputan caldera, Rindengan, and Manimporok (3.5 km ESE). Kawah Masem maar was formed in the W part of the caldera and contains a crater lake; sulfur has been extracted from fumarolic areas in the maar since 1938. Recent eruptions have originated at both the summit crater and Aeseput, a prominent NE-flank vent that formed in 1906 and was the source of intermittent major lava flows until 1924.