Partial resolution of sources of n-alkanes in the saline portion of the Parachute Creek Member, Green River Formation (Piceance Creek Basin, Colorado)

James W. Collister , Eric Lichtfouse (1) , Glenn Hieshima , John M. Hayes

1 ASD - Agronomy for Sustainable Development

Systematic variations in the 13C contents of individual extractable n-alkanes (C16–C29) can be modelled quantitatively and interpreted as indicating contributions from at least five distinct sources. These appear to be cyanobacterial, phytoplanktonic, chemoautotrophic bacterial, phytoplanktonic or heterotrophic bacterial (C20–C29), and vascular plants. Hydrous pyrolysis of related kerogens yields large quantities of additional n-alkanes with different and much more uniform δ values. The latter materials are apparently derived from the thermolysis of aliphatic biopolymers whose presence in the Green River Oil Shale has been recognized visually.

Mots clés: n-alkane carbon isotope ratios; Green River Formation; Parachute Creek Member; Piceance Creek Basin; cyanobacteria; hydrous pyrolysis; aliphatic biopolymers; organic matter sources

Domaines: Chimie analytique; Géochimie; Milieux et Changements globaux

James W. Collister, Eric Lichtfouse, Glenn Hieshima, John M. Hayes. Partial resolution of sources of n-alkanes in the saline portion of the Parachute Creek Member, Green River Formation (Piceance Creek Basin, Colorado). Organic Geochemistry, 1994, 21 (6/7), pp.645-659. ⟨10.1016/0146-6380(94)90010-8⟩. ⟨hal-00191115⟩