Lithospheric Structure of the West and Central African Rift System From Regional Three-Dimensional Gravity Modelling

Research Article| September 01, 2015 LITHOSPHERIC STRUCTURE OF THE WEST AND CENTRAL AFRICAN RIFT SYSTEM FROM REGIONAL THREE-DIMENSIONAL GRAVITY MODELLING A. EYIKE; A. EYIKE Department of Physics, Faculty of Science, University of Douala, PO Box 24157, Douala, Cameroon, e-mail: aeyike@gmail.com Search for other works by this author on: GSW Google Scholar J. EBBING J. EBBING Department of Geosciences, Christian-Albrechts-Universität, Kiel, Otto-Hahn-Platz 1. D-24118 Kiel, Germany, e-mail: jebbing@geophysik.uni-kiel.de Search for other works by this author on: GSW Google Scholar Author and Article Information A. EYIKE Department of Physics, Faculty of Science, University of Douala, PO Box 24157, Douala, Cameroon, e-mail: aeyike@gmail.com J. EBBING Department of Geosciences, Christian-Albrechts-Universität, Kiel, Otto-Hahn-Platz 1. D-24118 Kiel, Germany, e-mail: jebbing@geophysik.uni-kiel.de Publisher: Geological Society of South Africa First Online: 09 Mar 2017 Online ISSN: 1996-8590 Print ISSN: 1012-0750 © 2015 Geological Society of South Africa South African Journal of Geology (2015) 118 (3): 285–298. https://doi.org/10.2113/gssajg.118.3.285 Article history First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation A. EYIKE, J. EBBING; LITHOSPHERIC STRUCTURE OF THE WEST AND CENTRAL AFRICAN RIFT SYSTEM FROM REGIONAL THREE-DIMENSIONAL GRAVITY MODELLING. South African Journal of Geology 2015;; 118 (3): 285–298. doi: https://doi.org/10.2113/gssajg.118.3.285 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietySouth African Journal of Geology Search Advanced Search Abstract A three-dimensional interpretation of the central part of the West and Central African Rift System (WCARS) is presented using the Earth Gravity Model 2008 (EGM2008). The 3-D model presented here provides new insights into the regional lithospheric structure of the central sector of the WCARS. The 3-D model reveals a possible crustal thickness and density distribution beneath the rift system, and the depth extent of magmatic activity in the Benue Trough is revealed for the first time. Because of asthenospheric uplift, the crust under the Benue Trough is thinned. The zone of crustal thinning (<30 km) coincides with the trace of an intrusion beneath the trough, and the maximum of which is attained in the Yola Basin. The Adamawa and Kapsiki Plateaus, on the other hand, show by far the largest crustal thickness in the region (34 to 36 km). The inferred zone of intrusion coincides with the maximum gravity anomaly of the rift zone. The great depth (ca. 14 km) to the top of the intrusion along the rift may explain the absence of magmatism in the Benue Trough compared to the Cameroon Volcanic Line (CVL) or the East African Rift System (EARS). The relatively small nature of the intrusion leads to the conclusion that small-scale asthenospheric upwelling might be responsible for the thinning of the crust and subsequent rifting of the Benue Trough. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.