Report on Raung (Indonesia) — 1 July-7 July 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 1 July-7 July 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Raung (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 1 July-7 July 2015. Smithsonian Institution and US Geological Survey.
8.119°S, 114.056°E; summit elev. 3260 m
All times are local (unless otherwise noted)
Based on notices from the Ujung Padang MWO and PVMBG, satellite images, and pilot observations, the Darwin VAAC reported that during 1 and 3-7 July ash plumes from Raung rose to altitudes of 3.7-6.1 km (12,000-20,000 ft) a.s.l. and drifted 25-110 km E, ESE, and SE. According to news articles, flights in and out of an airport in Bali were cancelled due to ash emissions during 3-4 July. On 5 July BNPB reported that roaring was heard from continuous explosions and Strombolian activity at Raung. Dense white-and-gray plumes rose as high as 400 m and drifted SE. The Alert Level remained at 3 (on a scale of 1-4), and the public was reminded 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.