Microbial Reservoir Characterization: An Integration of Surface Geochemistry and Developmental Geology Data

Daniel Hitzman, James Tucker, and Brooks Rountree

Microbial Reservoir Characterization (MRC) integrates measurements of hydrocarbon-microseepage escaping from petroleum reservoirs with developmental geologic and engineering data for an enhanced identification of the subsurface reservoir fabric. Studies from mature producing fields demonstrate MRC technology can monitor subsurface fluid withdrawal patterns with microseepage patterns identified from surface soil samples. Areas of the reservoir in contact with producing wells, by-passed production, and reservoir heterogeneity characteristics can be identified. Microbial microseepage links the distribution of hydrocarbon traps with the continuity (compartments) of a reservoir, as well as locates areas prone to higher quality reserves. Upward, buoyancy driven forces controlling hydrocarbon microseepage is altered along pressure pathways streaming to production wells. In these cases, microseepage is essentially shut down and lower concentrations of gases reach the surface environment. Case studies from a variety of basin environments will be presented.

AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California