Mantle upwelling and initiation of rift segmentation beneath the Afar Depression
Hammond, James O.S. and Kendall, J.-M. and Stuart, G.W. and Ebinger, C.J. and Bastow, I.D. and Keir, D. and Ayele, A. and Belachew, M. and Goitom, B. and Ogubazghi, G. and Wright, T.J. (2013) Mantle upwelling and initiation of rift segmentation beneath the Afar Depression. Geology 41 (6), pp. 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 plume-induced 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 |
---|---|
School: | Birkbeck Faculties and Schools > Faculty of Science > School of Natural Sciences |
Depositing User: | Sarah Hall |
Date Deposited: | 19 May 2016 15:04 |
Last Modified: | 02 Aug 2023 17:23 |
URI: | https://eprints.bbk.ac.uk/id/eprint/15236 |
Statistics
Additional statistics are available via IRStats2.