Basement anisotropies along the western shoulder of the Kenya Rift and their relationship to Cenozoic rift structures

The Late Proterozoic Mozambique Belt in western Kenya is characterized by imbricated crustal stacks and steep E dipping foliation, generated during Tibetan-style collision and subsequent orogen-parallel sinistral shearing. During the final stages of orogenic evolution NW trending fault zones generated pseudotachylytes. Cenozoic rift faults exploit these anisotropies at different scales. The Kenya Rift follows the boundary between the Archean Tanzania Craton and the Mozambique Belt. The rift basins east of the Elgeyo and Nguruman Escarpments are bounded by E dipping normal faults that reactivated basement foliation and brittle shear zones.