Congruent Permian-Triassic δ238U records at Panthalassic and Tethyan sites: Confirmation of global-oceanic anoxia and validation of the U-isotope paleoredox proxy

Research Article| February 09, 2018 Congruent Permian-Triassic δ238U records at Panthalassic and Tethyan sites: Confirmation of global-oceanic anoxia and validation of the U-isotope paleoredox proxy Feifei Zhang; Feifei Zhang * 1School of Earth & Space Exploration, Arizona State University, Tempe, Arizona 85287, USA *E-mail: fzhang48@asu.edu; zhff414@hotmail.com Search for other works by this author on: GSW Google Scholar Thomas J. Algeo; Thomas J. Algeo 2Department of Geology, University of Cincinnati, Cincinnati, Ohio 45221, USA3State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, Hubei 430074, China4State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei 430074, China Search for other works by this author on: GSW Google Scholar Stephen J. Romaniello; Stephen J. Romaniello 1School of Earth & Space Exploration, Arizona State University, Tempe, Arizona 85287, USA Search for other works by this author on: GSW Google Scholar Ying Cui; Ying Cui 5Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA Search for other works by this author on: GSW Google Scholar Laishi Zhao; Laishi Zhao 3State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, Hubei 430074, China Search for other works by this author on: GSW Google Scholar Zhong-Qiang Chen; Zhong-Qiang Chen 4State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei 430074, China Search for other works by this author on: GSW Google Scholar Ariel D. Anbar Ariel D. Anbar 1School of Earth & Space Exploration, Arizona State University, Tempe, Arizona 85287, USA6School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Feifei Zhang * 1School of Earth & Space Exploration, Arizona State University, Tempe, Arizona 85287, USA Thomas J. Algeo 2Department of Geology, University of Cincinnati, Cincinnati, Ohio 45221, USA3State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, Hubei 430074, China4State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei 430074, China Stephen J. Romaniello 1School of Earth & Space Exploration, Arizona State University, Tempe, Arizona 85287, USA Ying Cui 5Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA Laishi Zhao 3State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, Hubei 430074, China Zhong-Qiang Chen 4State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, Hubei 430074, China Ariel D. Anbar 1School of Earth & Space Exploration, Arizona State University, Tempe, Arizona 85287, USA6School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, USA *E-mail: fzhang48@asu.edu; zhff414@hotmail.com Publisher: Geological Society of America Received: 08 Sep 2017 Revision Received: 16 Jan 2018 Accepted: 16 Jan 2018 First Online: 09 Feb 2018 Online Issn: 1943-2682 Print Issn: 0091-7613 © 2018 Geological Society of America Geology (2018) 46 (4): 327–330. https://doi.org/10.1130/G39695.1 Article history Received: 08 Sep 2017 Revision Received: 16 Jan 2018 Accepted: 16 Jan 2018 First Online: 09 Feb 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Feifei Zhang, Thomas J. Algeo, Stephen J. Romaniello, Ying Cui, Laishi Zhao, Zhong-Qiang Chen, Ariel D. Anbar; Congruent Permian-Triassic δ238U records at Panthalassic and Tethyan sites: Confirmation of global-oceanic anoxia and validation of the U-isotope paleoredox proxy. Geology 2018;; 46 (4): 327–330. doi: https://doi.org/10.1130/G39695.1 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 Oceanic anoxia has been proposed as a proximate cause of the end-Permian mass extinction (EPME), but evaluation of this hypothesis is hampered by limited detailed knowledge of its timing and extent. The recent development of uranium isotopes (δ238U) in carbonates as a global-ocean redox proxy provides new insights into this problem. Three earlier δ238U studies of Tethyan sections inferred development of extensive oceanic anoxia at the EPME. However, recent work raises concerns that diagenetic alteration may influence the reliability of δ238U records in bulk carbonate sediments. Here, we evaluate this possibility through δ238U analysis of a Permian-Triassic carbonate atoll section from the Panthalassic Ocean (Kamura, Japan) and comparison with existing δ238U profiles from the Tethys Ocean. The Kamura section exhibits a large negative δ238U shift across the EPME horizon identical both in timing and magnitude to those in Tethyan sections, demonstrating beyond a reasonable doubt that the negative seawater δ238U shift at the EPME was a global event, and that it was recorded by shallow carbonate facies globally. The robustness of the U-isotope proxy is further shown by the fact that a common global signal at the EPME was preserved despite major differences in the burial histories of Panthalassic and Tethyan sections, the former having been tectonically subducted and heated to greenschist metamorphic grade, whereas the latter accumulated in stable cratonic settings and experienced milder burial effects. Finally, we use leaching experiments to demonstrate that, although small-scale δ238U heterogeneity is common in both modern and ancient carbonates, it probably does not significantly affect bulk-carbonate δ238U trends. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.