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 Recent global tomography models show a continuous plume down to the core-mantle boundary beneath Kenya and a detached plume beneath Afar.  The interaction of the Afar plume with the Tethyan slab may be responsible for its detachment as shown in laboratory experiments.  A third plume between Kenya and Afar may have caused the Ethiopia-Yemen traps 30 Ma, now merging with the Afar plume.

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Deep earthquakes occur down to 700 km depth where pressure is up to two orders of magnitude greater than in the crust. Rupture characteristics and propagation mechanisms under those extreme conditions are still poorly constrained. We invert seismic waveforms for the spatial dimensions, duration and stress drop of deep‐focus earthquakes (Mw 6.7–7.7) in the Kuril subduction zone. We find stress drops of ∼1–10 MPa and rigidity‐corrected spatial dimensions and durations similar to crustal earthquakes. Radiated efficiency >1 is observed, suggesting that undershooting is prevalent in deep earthquakes, consistent with laboratory derived weakening mechanisms. Comparisons with subduction models suggest across‐slab propagation within regions with temperatures T < ∼ 1,000°C, similar to shallow events. Hence, despite different triggering mechanisms, the same physics seems to control the rupture propagation of both shallow and deep earthquakes.