Report on Dieng Volcanic Complex (Indonesia) — 30 July-5 August 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 July-5 August 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Dieng Volcanic Complex (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 30 July-5 August 2003. Smithsonian Institution and US Geological Survey.
Dieng Volcanic Complex
7.2°S, 109.879°E; summit elev. 2565 m
All times are local (unless otherwise noted)
Mud flowed from Dieng's Sileri crater during the night of 20 July, traveling as far as 25 m S of the crater rim. The temperature of the crater on 21 July was 74° C, which had not increased much since last measured. On 22 July the Alert Level at Dieng was raised to 2 (on a scale of 1-4). On 24 July at 0730 mud flowed as far as 50 m from the crater towards the N and E. Mud bubbled up to 1 m high in the center of the crater. No heightened seismicity was recorded during either mud-flow event. According to news reports, the crater was closed to tourists.
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.