Seismic Arrays to Study African Rift Initiation



Rifting of stable continents is a key element of plate tectonic cycles. In spite of numerous studies, the mechanism responsible for the initiation and evolution of rift valleys such as the East African Rift System (EARS) is still poorly understood, partly because most previous investigations focused on rift segments that were in the mature stage. Geodynamic modeling [Huismans et al., 2001] suggests that upwelling of the asthenosphere ubiquitously observed beneath mature rifts can either originate from thermal or dynamic anomalies in the deep mantle (active rifting) or be induced by thinning of the lithosphere from far-field stresses (passive rifting) [Sengor and Burke, 1978].