Report on Nyamulagira (DR Congo) — 24 May-30 May 2023
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 24 May-30 May 2023
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2023. Report on Nyamulagira (DR Congo) (Sennert, S, ed.). Weekly Volcanic Activity Report, 24 May-30 May 2023. Smithsonian Institution and US Geological Survey.
1.408°S, 29.2°E; summit elev. 3058 m
All times are local (unless otherwise noted)
On 28 May the Observatoire Volcanologique de Goma (OVG) reported that the lava flows on Nyamulagira’s upper W flank had begun to cool and solidify. By 29 May seismicity had returned to levels similar to those recorded before the 17 May increase in activity. Lava effusion continued but was confined to the summit crater; incandescence above the crater was periodically visible.
Geological Summary. Africa's most active volcano, Nyamulagira (also known as Nyamuragira), is a massive high-potassium basaltic shield about 25 km N of Lake Kivu and 13 km NNW of the steep-sided Nyiragongo volcano. The summit is truncated by a small 2 x 2.3 km caldera that has walls up to about 100 m high. Documented eruptions have occurred within the summit caldera, as well as from the numerous flank fissures and cinder cones. A lava lake in the summit crater, active since at least 1921, drained in 1938, at the time of a major flank eruption. Recent lava flows extend down the flanks more than 30 km from the summit as far as Lake Kivu; extensive lava flows from this volcano have covered 1,500 km2 of the western branch of the East African Rift.