Towards accurate numerical calibration of the Late Triassic: High-precision U-Pb geochronology constraints on the duration of the Rhaetian

Abstract

Research Article| July 01, 2014 Towards accurate numerical calibration of the Late Triassic: High-precision U-Pb geochronology constraints on the duration of the Rhaetian Jörn-Frederik Wotzlaw; Jörn-Frederik Wotzlaw * 1Section of Earth and Environmental Sciences, University of Geneva, 1201 Geneva, Switzerland *E-mail: joern.wotzlaw@unige.ch. Search for other works by this author on: GSW Google Scholar Jean Guex; Jean Guex 2Institute of Earth Sciences, University of Lausanne, 1015 Lausanne, Switzerland Search for other works by this author on: GSW Google Scholar Annachiara Bartolini; Annachiara Bartolini 3Muséum National d’Histoire Naturelle, 75005 Paris, France Search for other works by this author on: GSW Google Scholar Yves Gallet; Yves Gallet 4Equipe de Paléomagnétisme, Institut de Physique du Globe de Paris, 75238 Paris, France Search for other works by this author on: GSW Google Scholar Leopold Krystyn; Leopold Krystyn 5Institute of Paleontology, University of Vienna, 1090 Vienna, Austria Search for other works by this author on: GSW Google Scholar Christopher A. McRoberts; Christopher A. McRoberts 6Geology Department, State University of New York Cortland, Cortland, New York 13045, USA Search for other works by this author on: GSW Google Scholar David Taylor; David Taylor 7Department of Geological Sciences, University of Oregon, Eugene, Oregon 97403, USA Search for other works by this author on: GSW Google Scholar Blair Schoene; Blair Schoene 8Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA Search for other works by this author on: GSW Google Scholar Urs Schaltegger Urs Schaltegger 1Section of Earth and Environmental Sciences, University of Geneva, 1201 Geneva, Switzerland Search for other works by this author on: GSW Google Scholar Author and Article Information Jörn-Frederik Wotzlaw * 1Section of Earth and Environmental Sciences, University of Geneva, 1201 Geneva, Switzerland Jean Guex 2Institute of Earth Sciences, University of Lausanne, 1015 Lausanne, Switzerland Annachiara Bartolini 3Muséum National d’Histoire Naturelle, 75005 Paris, France Yves Gallet 4Equipe de Paléomagnétisme, Institut de Physique du Globe de Paris, 75238 Paris, France Leopold Krystyn 5Institute of Paleontology, University of Vienna, 1090 Vienna, Austria Christopher A. McRoberts 6Geology Department, State University of New York Cortland, Cortland, New York 13045, USA David Taylor 7Department of Geological Sciences, University of Oregon, Eugene, Oregon 97403, USA Blair Schoene 8Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA Urs Schaltegger 1Section of Earth and Environmental Sciences, University of Geneva, 1201 Geneva, Switzerland *E-mail: joern.wotzlaw@unige.ch. Publisher: Geological Society of America Received: 26 Feb 2014 Revision Received: 08 Apr 2014 Accepted: 10 Apr 2014 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2014 Geological Society of America Geology (2014) 42 (7): 571–574. https://doi.org/10.1130/G35612.1 Article history Received: 26 Feb 2014 Revision Received: 08 Apr 2014 Accepted: 10 Apr 2014 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 Jörn-Frederik Wotzlaw, Jean Guex, Annachiara Bartolini, Yves Gallet, Leopold Krystyn, Christopher A. McRoberts, David Taylor, Blair Schoene, Urs Schaltegger; Towards accurate numerical calibration of the Late Triassic: High-precision U-Pb geochronology constraints on the duration of the Rhaetian. Geology 2014;; 42 (7): 571–574. doi: https://doi.org/10.1130/G35612.1 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 Numerical calibration of the Late Triassic stages is arguably the most controversial issue in Mesozoic stratigraphy, despite its importance for assessing mechanisms of environmental perturbations and associated biologic consequences preceding the end-Triassic mass extinction. Here we report new chemical abrasion–isotope dilution–thermal ionization mass spectrometry zircon U-Pb dates for volcanic ash beds within the Aramachay Formation of the Pucara Group in northern Peru that place precise constraints on the age of the Norian-Rhaetian boundary (NRB) and the duration of the Rhaetian. The sampled ash bed–bearing interval is located just above the last occurrence of the bivalve Monotis subcircularis, placing this stratigraphic sequence in the uppermost Norian, perhaps ranging into the earliest Rhaetian. Zircon U-Pb dates of ash beds constrain the deposition age of this interval to be between 205.70 ± 0.15 Ma and 205.30 ± 0.14 Ma, providing precise constraints on the age of the NRB. Combined with previously published zircon U-Pb dates for ash beds bracketing the Triassic-Jurassic boundary, we estimate a duration of 4.14 ± 0.39 m.y. for the Rhaetian. This ends a prolonged controversy about the duration of this stage and has fundamental implications for the rates of paleoenvironmental deterioration that culminated in the end-Triassic mass extinction. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.