Location of the Nubia-Somalia boundary along the Southwest Indian Ridge

Research Article| April 01, 2002 Location of the Nubia-Somalia boundary along the Southwest Indian Ridge James Lemaux, II; James Lemaux, II 1Department of Earth Science, Rice University, Houston, Texas 77005, USA Search for other works by this author on: GSW Google Scholar Richard G. Gordon; Richard G. Gordon 1Department of Earth Science, Rice University, Houston, Texas 77005, USA Search for other works by this author on: GSW Google Scholar Jean-Yves Royer Jean-Yves Royer 2Centre National de la Recherche Scientifique, Institut Universitaire Européen de la Mer, Domaine Océaniques, F-29280 Plouzané, France Search for other works by this author on: GSW Google Scholar Author and Article Information James Lemaux, II 1Department of Earth Science, Rice University, Houston, Texas 77005, USA Richard G. Gordon 1Department of Earth Science, Rice University, Houston, Texas 77005, USA Jean-Yves Royer 2Centre National de la Recherche Scientifique, Institut Universitaire Européen de la Mer, Domaine Océaniques, F-29280 Plouzané, France Publisher: Geological Society of America Received: 21 Jun 2001 Revision Received: 12 Dec 2001 Accepted: 21 Dec 2001 First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2002) 30 (4): 339–342. https://doi.org/10.1130/0091-7613(2002)030<0339:LOTNSB>2.0.CO;2 Article history Received: 21 Jun 2001 Revision Received: 12 Dec 2001 Accepted: 21 Dec 2001 First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation James Lemaux, Richard G. Gordon, Jean-Yves Royer; Location of the Nubia-Somalia boundary along the Southwest Indian Ridge. Geology 2002;; 30 (4): 339–342. doi: https://doi.org/10.1130/0091-7613(2002)030<0339:LOTNSB>2.0.CO;2 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 northern boundary between the Nubian (West African) and Somalian (East African) plates is marked by the existence of the East African Rift, which is the locus of roughly east-west stretching due to the separation of these plates. South of ∼20°S, any expression of deformation or seismicity due to the relative motion of these two presumably distinct plates vanishes or is extremely subtle, although the boundary must continue until it intersects another plate boundary. Until recently, there were no observational limits on the location of that intersection, and the recent limits were very broad, being thousands of kilometers wide. Here, from an analysis of the locations of the old edge of magnetic anomaly 5 (which is over 11 Ma seafloor), we show that the main locus of deformation between Nubia and Somalia near the Southwest Indian Ridge over the past 11 m.y. can be no wider than a few hundred kilometers, from ∼100 km west of the Du Toit Fracture Zone to ∼50 km east of the Andrew Bain Fracture Zone complex. Deformation is most likely concentrated along a closely spaced set of several fracture zones known collectively as the Andrew Bain Fracture Zone complex, which is only ∼100 km wide. The displacement along the Nubia-Somalia boundary over the past 11 m.y. is 23 km ± 6 km (95% confidence limits), indicating a displacement rate of 2 mm/yr, much slower than typical rates of seafloor spreading and subduction, but comparable to that along the Owen fracture zone and Dalrymple trough, which separate the Arabian plate from the Indian plate, and along the Azores-Gibraltar line, which separates the Eurasian plate from the Nubian plate. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.