Report on Slamet (Indonesia) — June 1991
Bulletin of the Global Volcanism Network, vol. 16, no. 6 (June 1991)
Managing Editor: Lindsay McClelland.
Slamet (Indonesia) Plume emission follows harmonic tremor episodes
Please cite this report as:
Global Volcanism Program, 1991. Report on Slamet (Indonesia) (McClelland, L., ed.). Bulletin of the Global Volcanism Network, 16:6. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199106-263180.
7.242°S, 109.208°E; summit elev. 3428 m
All times are local (unless otherwise noted)
Harmonic tremor episodes (average frequency 2.5 Hz) began at 1730 on 24 June and were continuing as of early July. A dense 200-m-high plume was observed on 28 June. COSPEC measurements, started on 29 June, yielded SO2 fluxes of 66-87 t/d, compared to 30 t/d in 1988.
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.
Information Contacts: W. Modjo, VSI.