Seismic images of the Transition fault and the unstable Yakutat–Pacific–North American triple junction

Abstract

Research Article| May 01, 2013 Seismic images of the Transition fault and the unstable Yakutat–Pacific–North American triple junction S.P.S. Gulick; S.P.S. Gulick 1Institute for Geophysics, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas 78712, USA Search for other works by this author on: GSW Google Scholar R.S. Reece; R.S. Reece 1Institute for Geophysics, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas 78712, USA Search for other works by this author on: GSW Google Scholar G.L. Christeson; G.L. Christeson 1Institute for Geophysics, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas 78712, USA Search for other works by this author on: GSW Google Scholar H. van Avendonk; H. van Avendonk 1Institute for Geophysics, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas 78712, USA Search for other works by this author on: GSW Google Scholar L.L. Worthington; L.L. Worthington 2Department of Geology and Geophysics, School of Geosciences, Texas A&M University, College Station, Texas 77843, USA Search for other works by this author on: GSW Google Scholar T.L. Pavlis T.L. Pavlis 3Department of Geological Sciences, University of Texas at El Paso, El Paso, Texas 79968, USA Search for other works by this author on: GSW Google Scholar Geology (2013) 41 (5): 571–574. https://doi.org/10.1130/G33900.1 Article history received: 30 Jul 2012 rev-recd: 21 Nov 2012 accepted: 05 Dec 2012 first online: 09 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 S.P.S. Gulick, R.S. Reece, G.L. Christeson, H. van Avendonk, L.L. Worthington, T.L. Pavlis; Seismic images of the Transition fault and the unstable Yakutat–Pacific–North American triple junction. Geology 2013;; 41 (5): 571–574. doi: https://doi.org/10.1130/G33900.1 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 In southern Alaska, the Pacific plate and Yakutat terrane subduct beneath the North American plate along the Aleutian Trench and Pamplona zone, respectively, and are sliding past each other at minimal rates along the Transition fault. As the deformation front of the Pamplona zone stepped eastward during the Pliocene–Pleistocene, the Pacific–North American–Yakutat triple junction became unstable. Four recent seismic images reveal that the Transition fault changes from a single strike-slip boundary east of the deformation front to three strands that step increasingly seaward between the deformation front and the Aleutian Trench. The southern two strands deform the Pacific crust, and the outermost of these became increasingly convergent sometime since 1 Ma, as demonstrated by young growth strata. We propose that this internal deformation of the Pacific plate is an attempt to re-attain stability, which can only be reached by creating a tectonic boundary collinear with the Pamplona zone. The plate reorganization will result in initiation of subduction such that a portion of former Pacific crust will become accreted to the North American plate. Such accretion events caused by triple-junction instability may be an important mechanism for transferring oceanic crust to continental margins. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.