Microbial Communities in Oil Shales, Biodegraded and Heavy Oil Reservoirs, and Bitumen Deposits

  • Lisa M. GiegEmail author
Reference work entry
Part of the Handbook of Hydrocarbon and Lipid Microbiology book series (HHLM)


Oil shale (kerogen), light crude oil, heavy crude oil, and bitumen represent a sequence of fossil energy materials that range from “pre-oil” to “ultra-heavy oil” that were formed and/or then transformed over geological time in the Earth’s subsurface. Microorganisms can inhabit all of the deposits harboring these materials and have played a key role in transforming light crude oil to ultra-heavy bitumen. A majority of our understanding about how microbial life exists within and influences these hydrocarbon-associated subsurface environments comes from studying crude oil reservoirs, while comparatively little is known for oil shale or bitumen reservoirs. This chapter summarizes the knowledge to date on the microbial communities and their putative metabolic activities within these distinct petroliferous deposits.


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Authors and Affiliations

  1. 1.Department of Biological SciencesUniversity of CalgaryCalgaryCanada

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