Igwisi Hills

Igwisi Hills
Highest point
Elevation1,146 m (3,760 ft)
Coordinates4°53′13.18″S 31°56′4.46″E / 4.8869944°S 31.9345722°E / -4.8869944; 31.9345722
Geography
LocationTanzania
Geology
Rock agePleistocene?
Mountain typePyroclastic Cone
Last eruption10450 BC

The Igwisi Hills are a volcanic field in Kaliua District of Tabora Region of Tanzania. Three tuff cones are found there, one of which is associated with a lava flow. They are one of the few locations of possibly kimberlitic lava flows on Earth.

The volcanoes are located in the middle of the Tanzania craton, away from other Tanzanian volcanoes. There have been prior episodes of kimberlitic volcanism in the craton, however.

The age of the Igwisi Hills is poorly known but may be early Holocene-late Pleistocene in age. Some rainfall-induced chemical modification is found, and the hills have a unique vegetation profile.