Three teleseismic P-wave travel time data sets (KRISP 1985, 1989-1990; Kenya Broadband Seismic Experiment) have been inverted to obtain a new tomographic model of the upper mantle beneath the Kenya Rift. The model shows a 0.5-1.5% low velocity anomaly below the rift extending to about 150 km depth. Below ∼150 km depth, the anomaly broadens to the west toward the Tanzania Craton, suggesting a westward dip to the structure. Tomographic images to the south in Tanzania and to the north in Ethiopia also show westward dipping low velocity anomalies below depths of ∼150-200 km. The presence of westward dipping low velocity structures along much of the East African rift (Ethiopia, Kenya and Tanzania) is difficult to explain with a plume model and is consistent with some models of the African Superplume showing anomalous lower and upper mantle structure connecting at midmantle depths under the western side of East Africa.
|Original language||English (US)|
|Journal||Geophysical Research Letters|
|State||Published - Apr 16 2006|
All Science Journal Classification (ASJC) codes
- Earth and Planetary Sciences(all)