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Mantle Transition Zone Structure Beneath Kenya And Tanzania: More Evidence For A Deep-Seated Thermal Upwelling In The Mantle, Audrey D. Huerta, Andrew A. Nyblade, Angela M. Reusch

Geological Sciences Faculty Scholarship

Here we investigate the thermal structure of the mantle beneath the eastern Branch of the East African Rift system in Kenya and Tanzania. We focus on the structure of the mantle transition zone, as delineated by stacking of receiver functions. The top of the transition zone (the 410 km discontinuity) displays distinctive topography, and is systematically depressed beneath the rift in Kenya and northern Tanzania and adjacent volcanic fields. This depression is indicative of a localized ∼350 °C thermal anomaly. In contrast, the bottom of the transition zone (the 660 km discontinuity) is everywhere depressed. This region-wide depression is best …