Seamount subduction erosion in the Nankai Trough and its potential impact on the seismogenic zone

Abstract

Research Article| August 01, 2006 Seamount subduction erosion in the Nankai Trough and its potential impact on the seismogenic zone Nathan L.B. Bangs; Nathan L.B. Bangs 1Institute for Geophysics, University of Texas at Austin, 4412 Spicewood Springs Road, Austin, Texas 78759, USA Search for other works by this author on: GSW Google Scholar Sean P.S. Gulick; Sean P.S. Gulick 1Institute for Geophysics, University of Texas at Austin, 4412 Spicewood Springs Road, Austin, Texas 78759, USA Search for other works by this author on: GSW Google Scholar Thomas H. Shipley Thomas H. Shipley 1Institute for Geophysics, University of Texas at Austin, 4412 Spicewood Springs Road, Austin, Texas 78759, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Nathan L.B. Bangs 1Institute for Geophysics, University of Texas at Austin, 4412 Spicewood Springs Road, Austin, Texas 78759, USA Sean P.S. Gulick 1Institute for Geophysics, University of Texas at Austin, 4412 Spicewood Springs Road, Austin, Texas 78759, USA Thomas H. Shipley 1Institute for Geophysics, University of Texas at Austin, 4412 Spicewood Springs Road, Austin, Texas 78759, USA Publisher: Geological Society of America Received: 22 Nov 2005 Revision Received: 08 Mar 2006 Accepted: 12 Mar 2006 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2006) 34 (8): 701–704. https://doi.org/10.1130/G22451.1 Article history Received: 22 Nov 2005 Revision Received: 08 Mar 2006 Accepted: 12 Mar 2006 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Nathan L.B. Bangs, Sean P.S. Gulick, Thomas H. Shipley; Seamount subduction erosion in the Nankai Trough and its potential impact on the seismogenic zone. Geology 2006;; 34 (8): 701–704. doi: https://doi.org/10.1130/G22451.1 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 Seamount subduction along subduction-zone plate boundary thrusts has long been implicated as a mechanism for abrasion and tectonic erosion of the base of the overriding plate. However, tectonic erosion processes have not been examined in detail with high-quality three-dimensional (3-D) seismic reflection imaging. In 1999 we acquired 3-D seismic reflection data from the Nankai Trough subduction zone to image the plate boundary fault and the overlying accretionary wedge structure. Fortuitously, these data reveal a small (to 1 km high) basement ridge that has subducted to 7 km subseafloor. Updip from the basement ridge, a 1-km-thick sequence of sediment from the base of the accretionary wedge appears to be missing. We interpret these data as evidence for tectonic erosion of the base of the accretionary wedge following the basement ridge subduction. Tectonic erosion has removed more than 25 km3 from the updip edge of the seismogenic zone and carried it down into the seismogenic zone. The tectonically eroded sediments are presumed to enhance fault-zone fluid content, potentially reducing fault-zone effective stress, and may temporarily inhibit earthquake rupture potential. After the passage of the ridge the boundary fault returns to its former position in a period of enhanced underplating. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.