Detection of mantle earthquakes beneath the East African Rift

Abstract

Recordings from a temporary seismic network in the Rwenzori region of the East African Rift show seven earthquakes at a depth range between 53 and 60 km. Evidence from receiver functions indicates a crustal thickness of about 32 km in this region suggesting that the earthquakes are located well within the mantle beneath the rift. The occurrence of faulting at this depth is of relevance for models of continental-rift initiation and related deep magmatic processes.