Report on Slamet (Indonesia) — 3 June-9 June 2009
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 3 June-9 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, 3 June-9 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 26 May-4 June activity from Slamet fluctuated, but decreased overall. The number of earthquakes and the temperature of water in areas around the volcano were lower. Inflation and deflation fluctuated within a range of 2 cm. White plumes rose 100-750 high. During 5-7 June, activity was characterized by inflation and an increased number of earthquakes. During that time, white plumes were accompanied by ash emissions that rose 200-800 m from the crater, incandescent material was ejected 50-200 m above the crater, and booming noises were reported. The Alert Level remained at 3 (on a scale of 1-4).
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.