Report on Lewotobi (Indonesia) — 18 March-24 March 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 18 March-24 March 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Lewotobi (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 18 March-24 March 2015. Smithsonian Institution and US Geological Survey.
8.542°S, 122.775°E; summit elev. 1703 m
All times are local (unless otherwise noted)
PVMBG reported that white plumes were observed rising 15-20 m above Lewotobi during periods of clear weather from 1 February to17 March. Seismicity increased significantly on 13 March, especially volcanic earthquakes and shallow volcanic earthquakes; harmonic tremor, Tornillo events, and tectonic events were also detected. On 17 March the Alert Level was raised to 2 (on a scale of 1-4). Residents and tourists were warned not to approach the craters within a 1-km radius.
Geologic Background. The Lewotobi "husband and wife" twin volcano (also known as Lewetobi) in eastern Flores Island is composed of the Lewotobi Lakilaki and Lewotobi Perempuan stratovolcanoes. Their summits are less than 2 km apart along a NW-SE line. The conical Lakilaki has been frequently active during the 19th and 20th centuries, while the taller and broader Perempuan has erupted only twice in historical time. Small lava domes have grown during the 20th century in both of the crescentic summit craters, which are open to the north. A prominent flank cone, Iliwokar, occurs on the E flank of Perampuan.