Active displacement partitioning and arc-parallel extension of the Aleutian volcanic arc based on Global Positioning System geodesy and kinematic analysis

Abstract

Research Article| August 01, 2000 Active displacement partitioning and arc-parallel extension of the Aleutian volcanic arc based on Global Positioning System geodesy and kinematic analysis Hans G. Avé Lallemant; Hans G. Avé Lallemant 1Department of Geology and Geophysics, Rice University, Houston, Texas 77251-1892, USA Search for other works by this author on: GSW Google Scholar John S. Oldow John S. Oldow 2Department of Geological Sciences, University of Idaho, Moscow, Idaho 83844-3022, USA Search for other works by this author on: GSW Google Scholar Geology (2000) 28 (8): 739–742. https://doi.org/10.1130/0091-7613(2000)28<739:ADPAAE>2.0.CO;2 Article history received: 10 Jan 2000 rev-recd: 18 May 2000 accepted: 26 May 2000 first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Hans G. Avé Lallemant, John S. Oldow; Active displacement partitioning and arc-parallel extension of the Aleutian volcanic arc based on Global Positioning System geodesy and kinematic analysis. Geology 2000;; 28 (8): 739–742. doi: https://doi.org/10.1130/0091-7613(2000)28<739:ADPAAE>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentBy SocietyGeology Search Advanced Search Abstract Global Positioning System geodesy and structural analysis of parts of the Aleutian island chain support the interpretation of forearc migration westward along right-lateral transcurrent faults. Measured displacements are essentially arc parallel in the eastern (Unalaska Island) and western (Attu Island) parts of the arc and vary from 3.1 mm/yr to 31.4 mm/yr, respectively. At the center of the arc (Adak) subduction of the Amlia fracture zone disrupts the pattern of arc-parallel displacement and records an upper plate velocity of 9.6 mm/yr parallel to plate motion. Where active, displacement partitioning accommodates 30%–50% of the strike-slip component of plate convergence. In the area of impeded subduction partitioning ceases, suggesting that the process is sensitive to the degree of coupling across the plate-boundary megathrust. The differential arc-parallel displacements observed at the ends of the arc together with structural relations indicate substantial arc-parallel extension, which may play an important role in exhumation of high-pressure–low-temperature metamorphic rocks in ancient arc systems. You do not currently have access to this article.