Report on Raung (Indonesia) — 18 June-24 June 2014
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 18 June-24 June 2014
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2014. Report on Raung (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 18 June-24 June 2014. Smithsonian Institution and US Geological Survey.
8.119°S, 114.056°E; summit elev. 3260 m
All times are local (unless otherwise noted)
PVMBG reported that RSAM values from Raung showed an increase in energy during March-April. Additionally, during March-April, the daily number of volcanic earthquakes was dominated by tremor (with an increase in tremor amplitude); however, since the beginning of May, the number and the amplitude of tremor decreased.
During 1-17 June, when weather permitted, a weak solfatera plume was visible rising up to 100 m above the summit. On 17 June the Alert Level was lowered to 1 (on a scale of 1-4).
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.