Report on Dieng Volcanic Complex (Indonesia) — August 1998
Bulletin of the Global Volcanism Network, vol. 23, no. 8 (August 1998)
Managing Editor: Richard Wunderman.
Dieng Volcanic Complex (Indonesia) Plumes and earthquakes in early July
Please cite this report as:
Global Volcanism Program, 1998. Report on Dieng Volcanic Complex (Indonesia) (Wunderman, R., ed.). Bulletin of the Global Volcanism Network, 23:8. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199808-263200.
Dieng Volcanic Complex
7.2°S, 109.879°E; summit elev. 2565 m
All times are local (unless otherwise noted)
Seismicity increased in late June and early July. Earthquakes of M ~2 were felt locally three times on 2 July, and once on 4 July. An emission plume of white, moderately thick steam without ash issued from Sileri crater under low pressure to a height of 50 m. There was a moderate smell of sulfur. The crater lake water was clear to gray in color with temperatures varying between 54 and 94°C.
Geologic Background. The Dieng plateau in the highlands of central Java is renowned both for the variety of its volcanic scenery and as a sacred area housing Java's oldest Hindu temples, dating back to the 9th century CE. The Dieng volcanic complex consists of two or more stratovolcanoes and more than 20 small craters and cones of Pleistocene-to-Holocene age over a 6 x 14 km area. Prahu stratovolcano was truncated by a large Pleistocene caldera, which was subsequently filled by a series of dissected to youthful cones, lava domes, and craters, many containing lakes. Lava flows cover much of the plateau, but have not occurred in historical time, when activity has been restricted to minor phreatic eruptions. Toxic gas emissions are a hazard at several craters and have caused fatalities. The abundant thermal features and high heat flow make Dieng a major geothermal prospect.
Information Contacts: R. Sukhyar, Director, Volcanological Survey of Indonesia (VSI), Bandung, Indonesia (URL: http://www.vsi.esdm.go.id/).