Report on Merapi (Indonesia) — 15 November-21 November 2000
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 15 November-21 November 2000
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2000. Report on Merapi (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 15 November-21 November 2000. Smithsonian Institution and US Geological Survey.
7.54°S, 110.446°E; summit elev. 2910 m
All times are local (unless otherwise noted)
The VSI reported that during the week small explosions produced ash plumes that rose up to 430 m above Merapi's summit. High rains during 7 to 13 November caused landslides to occur in the upstream portion of Boyong river, Kaliurang. The river is on the S flank of Merapi and extends ~28 km map distance from the summit. The landslides killed one person and more landslides or lahars are expected during the current rainy season. The volcano is at Alert Level 2 (ranging from 1 to 4).
Geologic Background. Merapi, one of Indonesia's most active volcanoes, lies in one of the world's most densely populated areas and dominates the landscape immediately north of the major city of Yogyakarta. It is the youngest and southernmost of a volcanic chain extending NNW to Ungaran volcano. Growth of Old Merapi during the Pleistocene ended with major edifice collapse perhaps about 2,000 years ago, leaving a large arcuate scarp cutting the eroded older Batulawang volcano. Subsequent growth of the steep-sided Young Merapi edifice, its upper part unvegetated due to frequent activity, began SW of the earlier collapse scarp. Pyroclastic flows and lahars accompanying growth and collapse of the steep-sided active summit lava dome have devastated cultivated lands on the western-to-southern flanks and caused many fatalities.