Report on Nyamuragira (DR Congo) — October 1996
Bulletin of the Global Volcanism Network, vol. 21, no. 10 (October 1996)
Managing Editor: Richard Wunderman.
Nyamuragira (DR Congo) August seismic buildup and a 1 December eruption
Please cite this report as:
Global Volcanism Program, 1996. Report on Nyamuragira (DR Congo) (Wunderman, R., ed.). Bulletin of the Global Volcanism Network, 21:10. Smithsonian Institution.
1.408°S, 29.2°E; summit elev. 3058 m
All times are local (unless otherwise noted)
During August, Christoph Weber managed to visit Nyamuragira despite the hazard from armed groups roaming the region around the volcanoes. Although he found Nyamuragira quiet, Weber learned from Mahinda Kasereka of the Goma Volcano Observatory that seismicity had began to increase in August 1996.
An Associated Press story described lava flows escaping the crater on 1 December and reaching 10 km NW that evening. Satellite images in December as late as the 5th indicated reasonably dense plumes to ~12 km altitude. The eruption's impact on people in the region was uncertain. Further details will follow in a subsequent Bulletin.
Historical eruptions from Nyamuragira have occurred within the summit caldera and from numerous flank fissures and cinder cones. Twentieth century flank lava flows extend >30 km from the summit. In July 1994 a W-flank fissure emitted lava fountains, lava flows, and ash. For the past two and a half years this portion of Zaire's border had contained camps with hundreds of thousands of refugees; over a month ago these refugees fled to escape fighting.
Geologic Background. Africa's most active volcano, Nyamuragira, is a massive high-potassium basaltic shield about 25 km N of Lake Kivu. Also known as Nyamulagira, it has generated extensive lava flows that cover 1500 km2 of the western branch of the East African Rift. The broad low-angle shield volcano contrasts dramatically with the adjacent steep-sided Nyiragongo to the SW. The summit is truncated by a small 2 x 2.3 km caldera that has walls up to about 100 m high. Historical eruptions have occurred within the summit caldera, as well as from the numerous fissures and cinder cones on the flanks. A lava lake in the summit crater, active since at least 1921, drained in 1938, at the time of a major flank eruption. Historical lava flows extend down the flanks more than 30 km from the summit, reaching as far as Lake Kivu.
Information Contacts: Christoph Weber, Kruppstrasse 171, 42113 Wuppertal, Germany; Wafula Mifundi and Mahinda Kasereka, Goma Volcano Observatory, Departement de Geophysique, Centre de Recherche en Sciences Naturelles, Lwiro, D.S. Bukavu, Zaire; Associated Press.