Subduction-zone magnetic anomalies and implications for hydrated forearc mantle

Abstract

Research Article| June 01, 2005 Subduction-zone magnetic anomalies and implications for hydrated forearc mantle Richard J. Blakely; Richard J. Blakely 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USA Search for other works by this author on: GSW Google Scholar Thomas M. Brocher; Thomas M. Brocher 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USA Search for other works by this author on: GSW Google Scholar Ray E. Wells Ray E. Wells 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Richard J. Blakely 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USA Thomas M. Brocher 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USA Ray E. Wells 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USA Publisher: Geological Society of America Received: 07 Dec 2004 Revision Received: 22 Feb 2005 Accepted: 01 Mar 2005 First Online: 03 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 The Geological Society of America, Inc. Geology (2005) 33 (6): 445–448. https://doi.org/10.1130/G21447.1 Article history Received: 07 Dec 2004 Revision Received: 22 Feb 2005 Accepted: 01 Mar 2005 First Online: 03 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 Richard J. Blakely, Thomas M. Brocher, Ray E. Wells; Subduction-zone magnetic anomalies and implications for hydrated forearc mantle. Geology 2005;; 33 (6): 445–448. doi: https://doi.org/10.1130/G21447.1 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 Continental mantle in subduction zones is hydrated by release of water from the underlying oceanic plate. Magnetite is a significant byproduct of mantle hydration, and forearc mantle, cooled by subduction, should contribute to long-wavelength magnetic anomalies above subduction zones. We test this hypothesis with a quantitative model of the Cascadia convergent margin, based on gravity and aeromagnetic anomalies and constrained by seismic velocities, and find that hydrated mantle explains an important disparity in potential-field anomalies of Cascadia. A comparison with aeromagnetic data, thermal models, and earthquakes of Cascadia, Japan, and southern Alaska suggests that magnetic mantle may be common in forearc settings and thus magnetic anomalies may be useful in mapping hydrated mantle in convergent margins worldwide. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.