Department of Geosciences, Virginia Tech, Blacksburg, Virginia 24061, USA.

Department of Geological Sciences and Geological Engineering, Queen's University, Kingston, Ontario K7L 3N6, Canada

Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China

University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, Ontario L5L 1C6, Canada

Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, prospekt Akademika Koptyuga 3, Novosibirsk 630090, Russia

Department of Earth Sciences, Uppsala University, Villav?gen 16, SE 75236 Uppsala, Sweden

Department of Geoscience and NASA Astrobiology Institute, University of Wisconsin, Madison, Wisconsin 53706, USA