Report on Nyamuragira (DR Congo) — 30 April-6 May 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 April-6 May 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Nyamuragira (DR Congo). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 30 April-6 May 2003. Smithsonian Institution and US Geological Survey.
1.408°S, 29.2°E; summit elev. 3058 m
All times are local (unless otherwise noted)
A report issued on 2 May noted an inferred renewal of activity on Nyamuragira. Residents living in the villages of Katale and Tongo, the settlements closest to the volcano, reported rumblings on 30 April, in addition to clear noises of individual explosions. At the same time on 30 April the closest seismic station (Katale) recorded 18 clear explosion signals, directly followed by an important tectonic earthquake located beneath the volcano. In the next hours seismometers registered 7 type-C events and another important tectonic earthquake.
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.
Source: Observatoire Volcanologique de Goma (OVG)