Report on Raung (Indonesia) — 17 October-23 October 2012
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 17 October-23 October 2012
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2012. Report on Raung (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 17 October-23 October 2012. Smithsonian Institution and US Geological Survey.
8.119°S, 114.056°E; summit elev. 3260 m
All times are local (unless otherwise noted)
Seismicity at Raung increased on 17 October and remained elevated, prompting CVGHM to raise the Alert Level to 2 (on a scale of 1-4) on 18 October. During 18-22 October white plumes rose 50-75 m above the crater. Seismic activity increased significantly on 22 October. That same day the Alert Level was raised to 3. Visitors and residents were warned not to approach the crater within a 3-km radius.
Geologic Background. Raung, one of Java's most active volcanoes, is a massive stratovolcano in easternmost Java that was constructed SW of the rim of Ijen caldera. The unvegetated summit is truncated by a dramatic steep-walled, 2-km-wide caldera that has been the site of frequent historical eruptions. A prehistoric collapse of Gunung Gadung on the W flank produced a large debris avalanche that traveled 79 km, reaching nearly to the Indian Ocean. Raung contains several centers constructed along a NE-SW line, with Gunung Suket and Gunung Gadung stratovolcanoes being located to the NE and W, respectively.