Report on Nyamuragira (DR Congo) — 14 August-20 August 2002
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 14 August-20 August 2002
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2002. Report on Nyamuragira (DR Congo). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 14 August-20 August 2002. Smithsonian Institution and US Geological Survey.
1.408°S, 29.2°E; summit elev. 3058 m
All times are local (unless otherwise noted)
Scientists observing Nyamuragira, following the eruption that began on 25 July, found that on 6 August the lower part of a fracture on the volcano's N flank was active. They saw three very active lava fountains eject scoria about 100 m high and a very fast moving lava flow travel to the NE from a breach in the lowest part of the fracture. They estimated that about 3 million cubic meters of lava was being emitted per day. By the 7th, activity had dropped significantly, with only one weak lava fountain active and a decrease in the amount of tremor recorded.
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.
Sources: Observatoire Volcanologique de Goma (OVG), UN Office for the Coordination of Humanitarian Affairs (OCHA)