10Be imaging of sediment accretion and subduction along the northeast Japan and Costa Rica convergent margins

Abstract

Research Article| January 01, 2002 10Be imaging of sediment accretion and subduction along the northeast Japan and Costa Rica convergent margins J. Morris; J. Morris 1Department of Earth and Planetary Sciences, Washington University, St. Louis, Missouri 63130, USA Search for other works by this author on: GSW Google Scholar R. Valentine; R. Valentine 1Department of Earth and Planetary Sciences, Washington University, St. Louis, Missouri 63130, USA Search for other works by this author on: GSW Google Scholar T. Harrison T. Harrison 1Department of Earth and Planetary Sciences, Washington University, St. Louis, Missouri 63130, USA Search for other works by this author on: GSW Google Scholar Geology (2002) 30 (1): 59–62. https://doi.org/10.1130/0091-7613(2002)030<0059:BIOSAA>2.0.CO;2 Article history received: 17 May 2001 rev-recd: 26 Sep 2001 accepted: 01 Oct 2001 first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation J. Morris, R. Valentine, T. Harrison; 10Be imaging of sediment accretion and subduction along the northeast Japan and Costa Rica convergent margins. Geology 2002;; 30 (1): 59–62. doi: https://doi.org/10.1130/0091-7613(2002)030<0059:BIOSAA>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 Sediment accretion and subduction at convergent margins play an important role in the nature of hazardous interplate seismicity (the seismogenic zone) and the subduction recycling of volatiles and continentally derived materials to the Earth's mantle. Identifying and quantifying sediment accretion, essential for a complete mass balance across the margin, can be difficult. Seismic images do not define the processes by which a prism was built, and cored sediments may show disturbed magnetostratigraphy and sparse biostratigraphy. This contribution reports the first use of cosmogenic 10Be depth profiles to define the origin and structural evolution of forearc sedimentary prisms. Biostratigraphy and 10Be model ages generally are in good agreement for sediments drilled at Deep Sea Drilling Project Site 434 in the Japan forearc, and support an origin by imbricate thrusting for the upper section. Forearc sediments from Ocean Drilling Program Site 1040 in Costa Rica lack good fossil or paleomagnetic age control above the decollement. Low and homogeneous 10Be concentrations show that the prism sediments are older than 3–4 Ma, and that the prism is either a paleoaccretionary prism or it formed largely from slump deposits of apron sediments. Low 10Be in Costa Rican lavas and the absence of frontal accretion imply deeper sediment underplating or subduction erosion. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.