Report on Nyamuragira (DR Congo) — September 1992
Bulletin of the Global Volcanism Network, vol. 17, no. 9 (September 1992)
Managing Editor: Lindsay McClelland.
Nyamuragira (DR Congo) Continued lava production from fissure vent
Please cite this report as:
Global Volcanism Program, 1992. Report on Nyamuragira (DR Congo). In: McClelland, L. (ed.), Bulletin of the Global Volcanism Network, 17:9. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199209-223020.
1.408°S, 29.2°E; summit elev. 3058 m
All times are local (unless otherwise noted)
Activity continued in September with intermittent emission of lava and solid ejecta from Vent 20 (figure 12) . . . . During fieldwork on 11 September, lava fountaining was observed every 10-13 minutes. Lava flowed in a channel as much as 6-7 km N. Its front was advancing at 2-3 km/h on 12 September. Microtremor recorded at a nearby seismic station (Katale) had declined significantly.
[Continuous liquid lava extrusion continued until 24 November 1992. Short-lived lava fountaining at 5-10 day intervals took place at a fresh, previously inactive fissure, until 8 February 1993 (Zana and others, 1993; see 19:06).]
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: N. Zana, CRSN, Bukavu.