Report on Marapi (Indonesia) — 28 September-4 October 2022
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 28 September-4 October 2022
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2022. Report on Marapi (Indonesia) (Sennert, S, ed.). Weekly Volcanic Activity Report, 28 September-4 October 2022. Smithsonian Institution and US Geological Survey.
0.38°S, 100.474°E; summit elev. 2885 m
All times are local (unless otherwise noted)
PVMBG reported that seismicity at Marapi increased on 29 September, with 146 deep volcanic earthquakes recorded by the seismic network. Surficial activity showed no changes. The Alert Level remained at 1 (on a scale of 1-4).
Geological Summary. Gunung Marapi, not to be confused with the better-known Merapi volcano on Java, is Sumatra's most active volcano. This massive complex stratovolcano rises 2,000 m above the Bukittinggi Plain in the Padang Highlands. A broad summit contains multiple partially overlapping summit craters constructed within the small 1.4-km-wide Bancah caldera. The summit craters are located along an ENE-WSW line, with volcanism migrating to the west. More than 50 eruptions, typically consisting of small-to-moderate explosive activity, have been recorded since the end of the 18th century; no lava flows outside the summit craters have been reported in historical time.