Amazing stuff! Out of Africa!
"Research ... has uncovered evidence of rhythmic surges of molten mantle rock rising from deep within the Earth beneath Africa. These pulses are gradually tearing the continent apart and forming a new ocean.
The findings ... reveal that the Afar region in Ethiopia is underlain by a plume of hot mantle that pulses upward like a beating heart. ...
"We found that the mantle beneath Afar is not uniform or stationary—it pulses, and these pulses carry distinct chemical signatures. These ascending pulses of partially molten mantle are channeled by the rifting plates above. That's important for how we think about the interaction between Earth's interior and its surface." ...
The Afar region is a rare place on Earth where three tectonic rifts converge: the Main Ethiopian Rift, the Red Sea Rift, and the Gulf of Aden Rift. ..."
From the abstract:
"Mantle upwellings drive large-scale surface volcanism and facilitate continental breakup and ocean basin formation. However, the spatial characteristics and internal composition of these upwellings alongside how they are modified by plate tectonics are poorly resolved.
Afar, East Africa, is a classic triple junction comprising three rifts at various stages of evolution thought to be underlain by a mantle upwelling or plume, allowing examination of the controls on the mantle upwelling.
Here we present geochemical data from >130 samples of ‘young’ volcanoes spanning the rifts defining the triple junction to show that the underlying mantle comprises a single, asymmetric upwelling.
Using statistical modelling to integrate our data with existing geochemical and geophysical constraints, we suggest that Afar is fed by a spatially and chemically heterogeneous upwelling, which controls the composition and relative abundance of melt in all three rift arms.
We identify repetitive signatures in mantle compositions in rift regions, whose variability is a longer wavelength in faster-extending rift arms. This suggests more rapid channelized mantle flow occurs where rifting rates are higher and the plate is thinner, aiding flow of the upwelling towards the faster-spreading Red Sea Rift. Our findings demonstrate how the evolution of mantle upwellings is influenced by the dynamics of overriding plates."
Scientists detect deep Earth pulses beneath Africa (original news release)
Fig. 1: Variation in geochemical and geophysical properties around the Afar Triangle.
Fig. 6: Spatially heterogeneous nature of the mantle upwelling beneath Afar.
Active lava flows spilling out of the Erta Ale volcano in Afar, Ethiopia.
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