Karisimbi Volcano | John Seach


Democratic Republic of Congo / Rwanda

1.50 S, 29.45 E
summit elevation 4507 m

Karisimbi Volcano is located on the Democratic Republic of Congo / Rwanda border. It is the highest and largest volcano in the Virunga Range. Muntango pit crater is located south of the summit. Over 100 parasitic cones extend to the shores of Lake Kivu. The volcano contains a caldera (Branca).

Pumice, tuffs, and explosion breccias are located near the caldera of Karisimbi.

The largest lava flow at Karisimbi is almost 12 km long and covers an area of 23 sq km on the east flank of the volcano. It has a volume of more than 1 cubic km, distributed in two major branches. The lava flow has an average thickness of 40-60 m. The maximum thickness is over 140 m.

Summit Cone
The summit cone (Pic Bartholome) is steeper than the underlying volcano with slopes of 25-30 deg. It has the regular shape of a typical stratovolcano.

Pit Crater
South of the summit is located an elliptical pit crater with a diameter 1170 x 945 m. The floor of the crater is flat and covered with blocks.

The caldera is located east of the pit crater. It is circular and 2 km in diameter.

Lava Plain
The lava plain of Karisimbi volcano covers about 400 sq km and does not contain any watercourses. Most of the lava erupted from the pit crater and caldera. The lava resembles Hawaiian pahoehoe lava, and contains a smooth surface. The central part of the lava plain and on the southern side, lava tubes were formed. Lava tubes at Karisimbi volcano vary from a few hundred metres to several km long.

Adventive Volcanoes
Karisimbi volcano and lava plain contain 106 adventive cones, and has a density higher than Etna, Kilimanjaro, and Mauna Kea volcanoes. The adventive cones at Karisimbi volcano are 45% spatter and cinder cone.

Further reading
MacKay, Mary E., et al. "Thick lava flows of Karisimbi Volcano, Rwanda: insights from SIR-C interferometric topography." Bulletin of volcanology 60.4 (1998): 239-251.

De Mulder, M., et al. "The role of crustal contamination in the potassic suite of the Karisimbi volcano (Virunga, African Rift Valley)." Chemical geology 57.1-2 (1986): 117-136.

De Mulder, M. and Pasteels, P., 1986. K Ar geochronology of the Karisimbi volcano (Virunga, Rwanda-Zaire). Journal of African Earth Sciences (1983)5(6), pp.575-579.

Karisimbi Volcano Eruptions

No recent eruptions.