Paraná flood basalts: Rapid extrusion hypothesis confirmed by new 40Ar/39Ar results

Research Article| August 01, 2010 Paraná flood basalts: Rapid extrusion hypothesis confirmed by new 40Ar/39Ar results David S. Thiede; David S. Thiede * School of Earth Sciences, University of Queensland, St Lucia, Queensland 4072, Australia *E-mail: david.thiede@uq.edu.au. Search for other works by this author on: GSW Google Scholar Paulo M. Vasconcelos Paulo M. Vasconcelos School of Earth Sciences, University of Queensland, St Lucia, Queensland 4072, Australia Search for other works by this author on: GSW Google Scholar Author and Article Information David S. Thiede * School of Earth Sciences, University of Queensland, St Lucia, Queensland 4072, Australia Paulo M. Vasconcelos School of Earth Sciences, University of Queensland, St Lucia, Queensland 4072, Australia *E-mail: david.thiede@uq.edu.au. Publisher: Geological Society of America Received: 01 Dec 2009 Revision Received: 23 Mar 2010 Accepted: 25 Mar 2010 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2010 Geological Society of America Geology (2010) 38 (8): 747–750. https://doi.org/10.1130/G30919.1 Article history Received: 01 Dec 2009 Revision Received: 23 Mar 2010 Accepted: 25 Mar 2010 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 David S. Thiede, Paulo M. Vasconcelos; Paraná flood basalts: Rapid extrusion hypothesis confirmed by new 40Ar/39Ar results. Geology 2010;; 38 (8): 747–750. doi: https://doi.org/10.1130/G30919.1 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 duration of volcanism in the Paraná continental flood basalt (CFB) province, essential information to assess models of melt generation, eruption rates, continental breakup, and volcanism-driven extinction events, remains unresolved due to conflicting sets of 40Ar/39Ar geochronology data. Some results suggest that the Paraná CFB volcanism began at 134.7 ± 1 Ma and lasted <1 m.y. Another set of results reveals an extrusion interval of 11 m.y., from ca. 140 Ma to ca. 129 Ma. To resolve this controversy, we reanalyzed three of the exact hand specimens that previously yielded the oldest and youngest ages in the protracted 11 m.y. range. Our new ages are statistically indistinguishable from each other and the previous 134.7 ± 1 Ma result and indicate a short eruption event. A rapid extrusion for the Paraná CFB and the lack of a major cotemporal extinction event challenge proposed direct links between CFB volcanism and mass extinctions and refute petrological models that rely on a protracted extrusion of the Paraná CFB. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.