Upper mantle P-wave speed variations beneath Ethiopia and the origin of the Afar hotspot

Research Article| May 01, 2006 Upper mantle P-wave speed variations beneath Ethiopia and the origin of the Afar hotspot Margaret H. Benoit; Margaret H. Benoit 1Department of Geosciences, The Pennsylvania State University, University Park, Pennsylvania16803, USA Search for other works by this author on: GSW Google Scholar Andrew A. Nyblade; Andrew A. Nyblade 1Department of Geosciences, The Pennsylvania State University, University Park, Pennsylvania16803, USA Search for other works by this author on: GSW Google Scholar John C. VanDecar John C. VanDecar 2Department of Terrestrial Magnetism, Carnegie Institution, 1530 P Street NW, Washington, DC 20005, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Margaret H. Benoit 1Department of Geosciences, The Pennsylvania State University, University Park, Pennsylvania16803, USA Andrew A. Nyblade 1Department of Geosciences, The Pennsylvania State University, University Park, Pennsylvania16803, USA John C. VanDecar 2Department of Terrestrial Magnetism, Carnegie Institution, 1530 P Street NW, Washington, DC 20005, USA Publisher: Geological Society of America Received: 26 Sep 2005 Revision Received: 14 Nov 2005 Accepted: 17 Nov 2005 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2006) 34 (5): 329–332. https://doi.org/10.1130/G22281.1 Article history Received: 26 Sep 2005 Revision Received: 14 Nov 2005 Accepted: 17 Nov 2005 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Search Site Citation Margaret H. Benoit, Andrew A. Nyblade, John C. VanDecar; Upper mantle P-wave speed variations beneath Ethiopia and the origin of the Afar hotspot. Geology 2006;; 34 (5): 329–332. doi: https://doi.org/10.1130/G22281.1 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 SocietyGeology Search Advanced Search Abstract The Afar hotspot has long been attributed to one or more thermal upwellings in the mantle, in particular starting thermal plumes characterized by a head that spreads laterally beneath the lithosphere, and a tail. New P-wave tomography images of the upper mantle beneath Ethiopia reveal an elongated low wave speed region that is deep (>400 km) and wide (>500 km). The location of the low wave speed anomaly aligns with the Afar Depression and Main Ethiopian Rift in the uppermost mantle, but the center of the anomaly shifts to the west with depth. The shape, depth extent, and location of the low wave speed anomaly is not consistent with a starting thermal plume presently beneath the hotspot. Instead, the anomaly suggests that the hotspot may be the surface manifestation of a broad mantle upwelling connected to the African Superplume in the lower mantle beneath southern Africa. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.