Report on Slamet (Indonesia) — 24 June-30 June 2009
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 24 June-30 June 2009
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2009. Report on Slamet (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 24 June-30 June 2009. Smithsonian Institution and US Geological Survey.
7.242°S, 109.208°E; summit elev. 3428 m
All times are local (unless otherwise noted)
CVGHM reported that during 8-28 June tephra was ejected 50-700 m above Slamet's crater and incandescent material was ejected 50-300 m above the crater. Booming noises were reported. During 23-29 June, incandescence and ash emissions were not observed. On 29 June, CVGHM lowered the Alert Level for Slamet to 2 (on a scale of 1-4) because of decreased seismicity and emissions.
Geologic Background. Slamet, Java's second highest volcano at 3428 m and one of its most active, has a cluster of about three dozen cinder cones on its lower SE-NE flanks and a single cinder cone on the western flank. It is composed of two overlapping edifices, an older basaltic-andesite to andesitic volcano on the west and a younger basaltic to basaltic-andesite one on the east. Gunung Malang II cinder cone on the upper E flank on the younger edifice fed a lava flow that extends 6 km E. Four craters occur at the summit of Gunung Slamet, with activity migrating to the SW over time. Historical eruptions, recorded since the 18th century, have originated from a 150-m-deep, 450-m-wide, steep-walled crater at the western part of the summit and have consisted of explosive eruptions generally lasting a few days to a few weeks.