Reference Work Entry

Handbook of Hydrocarbon and Lipid Microbiology

pp 215-231

Abiogenic Hydrocarbon Production at the Geosphere-Biosphere Interface via Serpentinization Reactions

  • G. ProskurowskiAffiliated withWoods Hole Oceanographic Institution, Department of Marine Chemistry and Geochemistry

Abstract:

The production of hydrocarbons via mechanisms not associated with biological processes has far reaching implications to the fields of petroleum geochemistry, astrobiology, and the study of early life and life in extreme environments. Despite an intense focus on discovering abiotic hydrocarbon sources in natural settings, only a handful of sites convincingly suggest that abiotic organic synthesis occurs within the geosphere. Although experimental studies in aqueous settings clearly demonstrate the potential for abiotic synthesis, the scope of abiotic hydrocarbon production in natural settings has yet to be defined. As theoretical and experimental studies indicate that abiotic hydrocarbon synthesis is maximized in highly reducing environments, it is not surprising that the strongest evidence for abiotic organic synthesis in natural settings is associated with the alteration (serpentinization) of reduced mantle rocks. The crux of this topic is that currently there is no foolproof approach to distinguishing abiotic versus biotic organic synthesis. Thus, it is especially important to be cognizant of the possibilities and limitations of abiotic hydrocarbon production when considering a deep subsurface biosphere where the organic matter may be synthesized by both abiotic and biotic processes.