Report on Ibu (Indonesia) — March 2003
Bulletin of the Global Volcanism Network, vol. 28, no. 3 (March 2003)
Managing Editor: Edward Venzke.
Ibu (Indonesia) Infrared satellite data indicates activity during May-October 2001
Please cite this report as:
Global Volcanism Program, 2003. Report on Ibu (Indonesia). In: Venzke, E. (ed.), Bulletin of the Global Volcanism Network, 28:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN200303-268030.
1.488°N, 127.63°E; summit elev. 1325 m
All times are local (unless otherwise noted)
The last reported activity at Ibu included ash emission and mild ash explosions in September 1999. A May 2000 photo showed a lava dome covering the crater floor. MODIS data after May 2000 indicated thermal alerts during 28 May-3 October 2001 (figure 1). The series of alerts was consistent with continued inflation of, or extrusion onto, this dome. Note that the alert was barely above threshold, and it is likely that Ibu was just below detection threshold through 2002. A discussion of the MODIS technique was included in BGVN 28:01.
|Figure 1. MODIS thermal alerts on Ibu during 2001. Thermal alerts collated by Diego Coppola and David Rothery; data courtesy of the Hawaii Institute of Geophysics and Planetology's MODIS Thermal Alert Team.|
Geologic Background. The truncated summit of Gunung Ibu stratovolcano along the NW coast of Halmahera Island has large nested summit craters. The inner crater, 1 km wide and 400 m deep, contained several small crater lakes through much of historical time. The outer crater, 1.2 km wide, is breached on the north side, creating a steep-walled valley. A large parasitic cone is located ENE of the summit. A smaller one to the WSW has fed a lava flow down the W flank. A group of maars is located below the N and W flanks. Only a few eruptions have been recorded in historical time, the first a small explosive eruption from the summit crater in 1911. An eruption producing a lava dome that eventually covered much of the floor of the inner summit crater began in December 1998.
Information Contacts: Diego Coppola and David A. Rothery, Department of Earth Sciences, The Open University, Milton Keynes, MK7 6AA, UK. Thermal alerts courtesy of the HIGP MODIS Thermal Alerts Team (URL: http://modis.higp.hawaii.edu/).