Hammond, JOS, Bastow, ID, Kendall, JM et al. (8 more authors) (2013) Mantle upwelling and initiation of rift segmentation beneath the Afar Depression. Geology, 41 (6). 635 - 638. ISSN 0091-7613
Abstract
The Afar Depression, at the northern end of the East African Rift, is the only place on land where the transition from a plumeinduced continental breakup to seafloor spreading is active today. New images of seismic velocity structure, based on exceptional new data sets, show that the mantle plume that initiated rifting in Africa is absent beneath Afar today. The images are dominated by a major low-velocity feature at ~75 km depth closely mimicking the abrupt changes in rift axis orientation seen at the surface. This is likely associated with passive upwelling beneath the rift. Additional focused low-velocity anomalies show that small diapiric upwellings are present beneath major off-axis volcanoes. These multiple melting sources can explain the wide range of geochemical signatures seen in Afar. These images suggest that passive upwelling beneath Afar marks the initiation of rift segmentation as continental breakup progresses to seafloor spreading.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | (c) 2013, Geological Society of America. Gold Open Access paper. |
Keywords: | Continental break-up; East African Rift; Geochemical signatures; Low-velocity anomaly; Mantle upwellings; Multiple melting; Seafloor spreading; Seismic velocity structure |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 02 Aug 2013 11:49 |
Last Modified: | 22 Jan 2018 21:55 |
Published Version: | http://dx.doi.org/10.1130/G33925.1 |
Status: | Published |
Publisher: | Geological Society of America |
Identification Number: | 10.1130/G33925.1 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:76074 |