Desert pavement-coated surfaces in extreme deserts present the longest-lived landforms on Earth

Abstract

Research Article| May 01, 2009 Desert pavement–coated surfaces in extreme deserts present the longest-lived landforms on Earth Ari Matmon; Ari Matmon † 1The Institute of Earth Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel †E-mail: [e-mail]. Search for other works by this author on: GSW Google Scholar Ori Simhai; Ori Simhai 2The Institute of Earth Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel, and Geological Survey of Israel, 30 Malkhe Israel Street, Jerusalem 95501, Israel Search for other works by this author on: GSW Google Scholar Rivka Amit; Rivka Amit 3Geological Survey of Israel, 30 Malkhe Israel Street, Jerusalem 95501, Israel Search for other works by this author on: GSW Google Scholar Itai Haviv; Itai Haviv 4The Institute of Earth Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel Search for other works by this author on: GSW Google Scholar Naomi Porat; Naomi Porat 5Geological Survey of Israel, 30 Malkhe Israel Street, Jerusalem 95501, Israel Search for other works by this author on: GSW Google Scholar Eric McDonald; Eric McDonald 6Desert Research Institute, 2215 Raggio Parkway, Reno, Nevada 89512, USA Search for other works by this author on: GSW Google Scholar Lucilla Benedetti; Lucilla Benedetti 7Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement, Europôle Méditerranéen de l'Arbois, BP 80, Aix en Provence, cedex 04, 13545, France Search for other works by this author on: GSW Google Scholar Robert Finkel Robert Finkel 8Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Ari Matmon † 1The Institute of Earth Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel Ori Simhai 2The Institute of Earth Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel, and Geological Survey of Israel, 30 Malkhe Israel Street, Jerusalem 95501, Israel Rivka Amit 3Geological Survey of Israel, 30 Malkhe Israel Street, Jerusalem 95501, Israel Itai Haviv 4The Institute of Earth Sciences, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel Naomi Porat 5Geological Survey of Israel, 30 Malkhe Israel Street, Jerusalem 95501, Israel Eric McDonald 6Desert Research Institute, 2215 Raggio Parkway, Reno, Nevada 89512, USA Lucilla Benedetti 7Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement, Europôle Méditerranéen de l'Arbois, BP 80, Aix en Provence, cedex 04, 13545, France Robert Finkel 8Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA †E-mail: [e-mail]. Publisher: Geological Society of America Received: 26 Feb 2008 Revision Received: 15 Jul 2008 Accepted: 28 Jul 2008 First Online: 03 Oct 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 2009 Geological Society of America GSA Bulletin (2009) 121 (5-6): 688–697. https://doi.org/10.1130/B26422.1 Article history Received: 26 Feb 2008 Revision Received: 15 Jul 2008 Accepted: 28 Jul 2008 First Online: 03 Oct 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Ari Matmon, Ori Simhai, Rivka Amit, Itai Haviv, Naomi Porat, Eric McDonald, Lucilla Benedetti, Robert Finkel; Desert pavement–coated surfaces in extreme deserts present the longest-lived landforms on Earth. GSA Bulletin 2009;; 121 (5-6): 688–697. doi: https://doi.org/10.1130/B26422.1 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 SocietyGSA Bulletin Search Advanced Search Abstract All exposed rocks on Earth's surface experience erosion; the fastest rates are documented in rapidly uplifted monsoonal mountain ranges, and the slowest occur in extreme cold or warm deserts—millennial submeter-scale erosion may be approached only in the latter. The oldest previously reported exposure ages are from boulders and clasts of resistant lithologies lying at the surface, and the slowest reported erosion rates are derived from bedrock outcrops or boulders that erode more slowly than their surroundings; thus, these oldest reported ages and slowest erosion rates relate to outstanding features in the landscape, while the surrounding landscape may erode faster and be younger. We present erosion rate and exposure age data from the Paran Plains, a typical environment in the Near East where vast abandoned alluvial surfaces (102–104 km2) are covered by well-developed desert pavements. These surfaces may experience erosion rates that are slower than those documented elsewhere on our planet and can retain their original geometry for more than 2 m.y. Major factors that reduce erosion converge in these regions: extreme hyperaridity, tectonic stability, flat and horizontal surfaces (i.e., no relief), and effective surface armoring by a clast mosaic of highly resistant lithology. The 10Be concentrations in amalgamated desert pavement chert clasts collected from abandoned alluvial surfaces in the southern Negev, Israel (representing the Sahara-Arabia Deserts), indicate simple exposure ages of 1.5–1.8 Ma or correspond to maximum erosion rates of 0.25–0.3 m m.y.−1. The 36Cl in carbonate clasts, from the same pavement, weathers faster than the chert and yields simple exposure ages of 430–490 ka or maximum erosion rates of 0.7–0.8 m m.y.−1. These ages and rates are exceptional because they represent an extensive landform. The 10Be concentrations from samples collected at depth and optically stimulated luminescence (OSL) dating reveal a two-stage colluvial deposition history followed by eolian addition of 40 cm of silt during the past 170 k.y. Our results highlight the efficiency of desert pavement armor in protecting rocks from erosion and preserving such geomorphic surfaces for millions of years. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.