A Cryogenian chronology: Two long-lasting synchronous Neoproterozoic glaciations

Research Article| May 01, 2015 A Cryogenian chronology: Two long-lasting synchronous Neoproterozoic glaciations Alan D. Rooney; Alan D. Rooney 1Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Search for other works by this author on: GSW Google Scholar Justin V. Strauss; Justin V. Strauss 1Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Search for other works by this author on: GSW Google Scholar Alan D. Brandon; Alan D. Brandon 2Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas 77204, USA Search for other works by this author on: GSW Google Scholar Francis A. Macdonald Francis A. Macdonald 1Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Alan D. Rooney 1Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Justin V. Strauss 1Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Alan D. Brandon 2Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas 77204, USA Francis A. Macdonald 1Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Publisher: Geological Society of America Received: 09 Dec 2014 Revision Received: 05 Mar 2015 Accepted: 05 Mar 2015 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2015 Geological Society of America Geology (2015) 43 (5): 459–462. https://doi.org/10.1130/G36511.1 Article history Received: 09 Dec 2014 Revision Received: 05 Mar 2015 Accepted: 05 Mar 2015 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Alan D. Rooney, Justin V. Strauss, Alan D. Brandon, Francis A. Macdonald; A Cryogenian chronology: Two long-lasting synchronous Neoproterozoic glaciations. Geology 2015;; 43 (5): 459–462. doi: https://doi.org/10.1130/G36511.1 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 The snowball Earth hypothesis predicts globally synchronous glaciations that persisted on a multimillion year time scale. Geochronological tests of this hypothesis have been limited by a dearth of reliable age constraints bracketing these events on multiple cratons. Here we present four new Re-Os geochronology age constraints on Sturtian (717–660 Ma) and Marinoan (635 Ma termination) glacial deposits from three different paleocontinents. A 752.7 ± 5.5 Ma age from the base of the Callison Lake Formation in Yukon, Canada, confirms nonglacial sedimentation on the western margin of Laurentia between ca. 753 and 717 Ma. Coupled with a new 727.3 ± 4.9 Ma age directly below the glacigenic deposits of the Grand Conglomerate on the Congo craton (Africa), these data refute the notion of a global ca. 740 Ma Kaigas glaciation. A 659.0 ± 4.5 Ma age directly above the Maikhan-Uul diamictite in Mongolia confirms previous constraints on a long duration for the 717–660 Ma Sturtian glacial epoch and a relatively short nonglacial interlude. In addition, we provide the first direct radiometric age constraint for the termination of the Marinoan glaciation in Laurentia with an age of 632.3 ± 5.9 Ma from the basal Sheepbed Formation of northwest Canada, which is identical, within uncertainty, to U-Pb zircon ages from China, Australia, and Namibia. Together, these data unite Re-Os and U-Pb geochronological constraints and provide a refined temporal framework for Cryogenian Earth history. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.