Appendix D: Late Cretaceous (Maastrichtian) shallow water hydrocarbon seeps from Snow Hill and Seymour Islands, James Ross Basin, Antarctica Crispin T.S. Littlea*, Daniel Birgelb, Adrian J. Boycec, J. Alistair Cramed, Jane E. Francisd, Steffen Kiele, Jörn Peckmannb, Duncan Pirrief, Gavyn K. Rollinsong and James D. Wittsa aSchool of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK bDepartment of Geodynamics and Sedimentology, Center for Earth Sciences, University of Vienna, 1090 Vienna, Austria cSUERC, Rankine Avenue, Scottish Enterprise Technology Park, East Kilbride, G75 0QF, UK dBritish Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, UK eGeoscience Center, Georg-August University of Göttingen, Geobiology Group, Goldschmidtstrasse 3, 37077 Göttingen, Germany fHelford Geoscience LLP, Menallack Farm, Trelowarren Mill Barn, Mawgan, Helston, Cornwall, TR2 6AE, UK gCamborne School of Mines, CEMPS, University of Exeter, Penryn Campus, Cornwall TR10 9FE, UK *Corresponding author; telephone/fax number: +44 (0)113 3436621/+44 (0)113 343 5259; email address:
[email protected]. D1: Abstract Fossil hydrocarbon seeps are present in latest Cretaceous (Maastrichtian) volcaniclastic shallow shelf sediments exposed on Snow Hill and Seymour Islands, James Ross Basin, Antarctica. The seeps occur in the Snow Hill Island Formation on Snow Hill Island and are manifest as large-sized, cement- rich carbonate bodies, containing abundant thyasirid bivalves and rarer ammonites and solemyid bivalves. These bodies have typical seep cement phases, with δ13C values between 20.4 and 10.7‰ and contain molecular fossils indicative of terrigenous organic material and the micro-organisms involved in the anaerobic oxidation of methane, including methanotrophic archaea and sulphate-reducing bacteria.