Orogen-parallel extension and exhumation enhanced by denudation in the trans-Himalayan Arun River gorge, Ama Drime Massif, Tibet-Nepal

Abstract

Research Article| July 01, 2008 Orogen-parallel extension and exhumation enhanced by denudation in the trans-Himalayan Arun River gorge, Ama Drime Massif, Tibet-Nepal Micah J. Jessup; Micah J. Jessup * 1Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee 37996, USA * E-mail: [e-mail]. Search for other works by this author on: GSW Google Scholar Dennis L. Newell; Dennis L. Newell 2Hydrology, Geochemistry and Geology Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA Search for other works by this author on: GSW Google Scholar John M. Cottle; John M. Cottle 3Department of Earth Sciences, University of Oxford, Oxford OX1 3PR, UK Search for other works by this author on: GSW Google Scholar Aaron L. Berger; Aaron L. Berger 4Department of Geosciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA Search for other works by this author on: GSW Google Scholar James A. Spotila James A. Spotila 4Department of Geosciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA Search for other works by this author on: GSW Google Scholar Geology (2008) 36 (7): 587–590. https://doi.org/10.1130/G24722A.1 Article history received: 28 Dec 2007 rev-recd: 04 Mar 2008 accepted: 11 Mar 2008 first online: 02 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 Micah J. Jessup, Dennis L. Newell, John M. Cottle, Aaron L. Berger, James A. Spotila; Orogen-parallel extension and exhumation enhanced by denudation in the trans-Himalayan Arun River gorge, Ama Drime Massif, Tibet-Nepal. Geology 2008;; 36 (7): 587–590. doi: https://doi.org/10.1130/G24722A.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 Focused denudation and mid-crustal flow are coupled in many active tectonic settings, including the Himalaya, where exhumation of mid-crustal rocks accommodated by thrust faults and low-angle detachment systems during crustal shortening is well documented. New structural and (U-Th)/He apatite data from the Mount Everest region demonstrate that the trans-Himalayan Ama Drime Massif has been exhumed at a minimum rate of ~1 mm/yr between 1.5 and 3.0 Ma during orogen-parallel extension. The Ama Drime Massif offsets the South Tibetan detachment system, and therefore the South Tibetan detachment system is no longer capable of accommodating south-directed mid-crustal flow or coupling it with focused denudation. Previous investigations interpreted the NNE-SSW–striking shear zone on the west side of the Ama Drime Massif as the Main Central thrust zone; however, our data show that the Ama Drime Massif is bounded on either side by 100–300-m-thick normal-sense shear zone and detachment systems that are kinematically linked to young brittle faults that offset Quaternary deposits and record active orogen-parallel extension. When combined with existing data, these results suggest that the Ama Drime Massif was exhumed during orogen-parallel extension that was enhanced by, or potentially coupled with, denudation in the trans-Himalayan Arun River gorge. This model provides important insights into the mechanisms that exhumed trans-Himalayan antiformal structures during orogen-parallel extension along the southern margin of the Tibetan Plateau. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.