Lewi, E, Keir, D, Birhanu, Y et al. (4 more authors) (2015) Use of a high-precision gravity survey to understand the formation of oceanic crust and the role of melt at the southern Red Sea rift in Afar, Ethiopia. Geological Society, London, Special Publications (420). ISSN 0305-8719
Abstract
The Red Sea arm of the triple junction in northeastern Ethiopia provides an opportunity to investigate rift-forming processes at divergent boundaries. In an attempt to study the subsurface, especially the distribution and role of melt in the rifting process, we carried out a high-precision gravity survey with a mean-square error of 0.011 mgal, assisted by differential global positioning system measurements. The profile is 162 km long and strikes ENE–WSW across the southern part of the Red Sea rift at a latitude of approximately 11.75° N. Modelling of the Bouguer anomaly, constrained by a priori information, showed detailed in-rift variations in the crustal structure and the distribution of melt beneath the rift axis. Our interpretation suggested that the process of continental break-up is governed by crustal stretching and rifting accompanied by the emplacement of melt into the lower crust above a lower density upper mantle. In addition, we interpreted the thickness of the crust beneath this part of the rift axis to be 25 km. The subsurface distribution of density beneath the profile shows that the south-central part of the Red Sea rift has modified thinned crust, intruded by high-density material, which resembles the crust formed during seafloor spreading.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2015 The Author(s). Published by The Geological Society of London. This article is published under the terms of the CC-BY 3.0 license. |
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) > Inst of Geophysics and Tectonics (IGT) (Leeds) |
Funding Information: | Funder Grant number NERC No External Reference NERC NE/E007414/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 18 Dec 2015 12:45 |
Last Modified: | 18 Dec 2015 12:45 |
Published Version: | http://dx.doi.org/10.1144/SP420.13 |
Status: | Published |
Publisher: | The Geological Society of London |
Identification Number: | 10.1144/SP420.13 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:92973 |