Abstract

The kinematics of the East African Rift ( EAR) is the least well-known of all major plate boundaries. Here, we show that present-day data ( a GPS+DORIS geodetic solution and earthquake slip vectors) are consistent with 3.2 Myr-average spreading rates and transform-fault azimuths along the Southwest Indian Ridge and support a kinematic model that includes three subplates ( Victoria, Rovuma, and Lwandle) between Nubia and Somalia. Continental rifting in the EAR appears to involve localized strain along narrow rift structures that isolate large lithospheric blocks.