Complex shear wave velocity structure imaged beneath Africa and Iceland

A model of three-dimensional shear wave velocity variations in the mantle reveals a tilted low velocity anomaly extending from the core-mantle boundary (CMB) region beneath the southeastern Atlantic Ocean into the upper mantle beneath eastern Africa. This anomaly suggests that Cenozoic flood basalt...

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Bibliographic Details
Published in:Science
Main Authors: Ritsema, J, van Heijst, H, Woodhouse, J
Format: Article in Journal/Newspaper
Language:English
Published: 2016
Subjects:
Online Access:https://doi.org/10.1126/science.286.5446.1925
https://ora.ox.ac.uk/objects/uuid:a2c7cdc3-4a6e-4702-a385-94ceaf5e25b6
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Summary:A model of three-dimensional shear wave velocity variations in the mantle reveals a tilted low velocity anomaly extending from the core-mantle boundary (CMB) region beneath the southeastern Atlantic Ocean into the upper mantle beneath eastern Africa. This anomaly suggests that Cenozoic flood basalt volcanism in the Afar region and active rifting beneath the East African Rift is linked to an extensive thermal anomaly at the CMB more than 45 degrees away. In contrast, a low velocity anomaly beneath Iceland is confined to the upper mantle.