Thrust-type subduction-zone earthquakes and seamount asperities: A physical model for seismic rupture 论文

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Research Article| July 01, 1992 Thrust-type subduction-zone earthquakes and seamount asperities: A physical model for seismic rupture Mark Cloos Mark Cloos 1Department of Geological Sciences and Institute for Geophysics, University of Texas, Austin, Texas 78713-7909 Search for other works by this author on: GSW Google Scholar Geology (1992) 20 (7): 601–604. https://doi.org/10.1130/0091-7613(1992)020<0601:TTSZEA>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Mark Cloos; Thrust-type subduction-zone earthquakes and seamount asperities: A physical model for seismic rupture. Geology 1992;; 20 (7): 601–604. doi: https://doi.org/10.1130/0091-7613(1992)020<0601:TTSZEA>2.3.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 A thrust-type subduction-zone earthquake of Mw 7.6 ruptures an area of ∼6000 km2, has a seismic slip of ∼1 m, and is nucleated by the rupture of an asperity ∼25 km across. A model for thrust-type subduction-zone seismicity is proposed in which basaltic seamounts jammed against the base of the overriding plate act as strong asperities that rupture by stick-slip faulting. A Mw 7.6 event would correspond to the near-basal rupture of a ∼2-km-tall sea-mount. The base of the seamount is surrounded by a low shear- strength layer composed ofsubducting sediment that also deforms between seismic events by distributed strain (viscous flow). Planar faults form in this layer as the seismic rupture propagates out of the seamount at speeds of kilometres per second. The faults in the shear zone are disrupted after the event by aseismic, slow viscous flow of the subducting sediment layer. Consequently, the extent of fault rupture varies for different earthquakes nucleated at the same seamount asperity because new fault surfaces form in the surrounding subducting sediment layer during each fast seismic rupture. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.