Increased seismicity was recorded in November 1975, but no eruption occurred. The last eruption, October-November 1982, produced lava fountaining from a radial fissure 6.5 kilometers southwest of the summit and a lava flow that moved 12 kilometers down the southwest flank. Two towns were evacuated, and tephra caused damage to plantations. Most African volcanoes result from hot spots , rifting in East Africa, or a combination of the two. The East African rift , one of the world's most dramatic extensional structures, has produced the continent's highest and lowest volcanoes, ranging from massive Kilimanjaro to vents in Ethiopia's Danakil Depression that lie below sea level.
Most African volcanoes result from hot spots , rifting in East Africa, or a combination of the two.
The East African rift , one of the world's most dramatic extensional structures, has produced the continent's highest and lowest volcanoes, ranging from massive Kilimanjaro to vents in Ethiopia's Danakil Depression that lie below sea level. Virunga National Park, Nyamuragira and Nyiragongo , are responsible for nearly two-fifths of Africa's historical eruptions. The Lake Nyos event on 21 August 1986 caused at least 1,700 fatalities. The emission of around 1 cubic kilometer of magmatic CO2 has been attributed to overturn of stratified lake waters as a result of a non-volcanic process, or to phreatic explosions or injection of hot gas into the lake.