Extensive Early Cretaceous (Albian) methane seepage on Ellef Ringnes Island, Canadian High Arctic

Abstract

Research Article| July 01, 2017 Extensive Early Cretaceous (Albian) methane seepage on Ellef Ringnes Island, Canadian High Arctic Krista Williscroft; Krista Williscroft 1Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada Search for other works by this author on: GSW Google Scholar Stephen E. Grasby; Stephen E. Grasby † 1Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada2Geological Survey of Canada, Natural Resources Canada, 3303 33rd Street NW, Calgary, Alberta T2L 2A7, Canada †Corresponding author: steve.grasby@canada.ca. Search for other works by this author on: GSW Google Scholar Benoit Beauchamp; Benoit Beauchamp 1Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada Search for other works by this author on: GSW Google Scholar Crispin T.S. Little; Crispin T.S. Little 3School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK Search for other works by this author on: GSW Google Scholar Keith Dewing; Keith Dewing 1Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada2Geological Survey of Canada, Natural Resources Canada, 3303 33rd Street NW, Calgary, Alberta T2L 2A7, Canada Search for other works by this author on: GSW Google Scholar Daniel Birgel; Daniel Birgel 4Institute of Geology, University of Hamburg, 20146 Hamburg, Germany Search for other works by this author on: GSW Google Scholar Terry Poulton; Terry Poulton 2Geological Survey of Canada, Natural Resources Canada, 3303 33rd Street NW, Calgary, Alberta T2L 2A7, Canada Search for other works by this author on: GSW Google Scholar Krzysztof Hryniewicz Krzysztof Hryniewicz 5Institute of Paleobiology, Polish Academy of Sciences, ul. Twarda 51/55, 00-818 Warszawa, Poland Search for other works by this author on: GSW Google Scholar GSA Bulletin (2017) 129 (7-8): 788–805. https://doi.org/10.1130/B31601.1 Article history received: 27 Jun 2016 rev-recd: 20 Dec 2016 accepted: 21 Feb 2017 first online: 06 Jul 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Krista Williscroft, Stephen E. Grasby, Benoit Beauchamp, Crispin T.S. Little, Keith Dewing, Daniel Birgel, Terry Poulton, Krzysztof Hryniewicz; Extensive Early Cretaceous (Albian) methane seepage on Ellef Ringnes Island, Canadian High Arctic. GSA Bulletin 2017;; 129 (7-8): 788–805. doi: https://doi.org/10.1130/B31601.1 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 During field mapping of Ellef Ringnes Island, Canadian Arctic Archipelago, 139 isolated Early Cretaceous methane seep deposits were found from 75 field sites. Stable isotopes of the carbonates have values of δ13C = –47‰ to –35‰ and δ18O = –4.0‰ to +0.7‰. Isoprenoids in organics from one of the seeps are significantly depleted in 13C, with the most negative δ13C value of –118‰ and –113‰ for 2,6,10,15,19-pentamethylicosane (PMI) and phytane/crocetane, respectively. These values indicate an origin through methane oxidation, consistent with biomarkers that are characteristic for anaerobic methanotrophic archaea within the seep deposits, accompanied by terminally branched fatty acids showing similar 13C values (–92‰) sourced from sulfate-reducing bacteria. The seep deposits contain a moderate-diversity macrofaunal assemblage comprising ammonites, bivalves, gastropods, scaphopods, “vestimentiferan” worm tubes, and brachiopods. The assemblage is dominated numerically by species that probably had chemosymbionts. The seep deposits formed in the subsurface within strong redox zones, in an otherwise normal marine setting, characterized by oxic waters at high paleolatitudes.While geographically widespread over an area of ∼10,000 km2, seep deposits on Ellef Ringnes Island occur in a narrow stratigraphic horizon, suggesting a large release of biogenic methane occurred over a brief period of time. This gas release was coincident with a transition from a cold to warm climate during the latest early Albian, and we hypothesize that this may have been related to gas hydrate release. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.