Formation evaluation and characterization of shale-gas reservoirs by means of core and wireline data integration

Formation evaluation using wireline logs in shale-gas or source-rock reservoirs can be complicated by the presence of total organic carbon (TOC) and, at times, rapidly varying mineralogy. If not properly accounted for, both can result in erroneous calculations of porosity and free-gas and adsorbed-gas volume. When core data, such as mineralogy, porosity, TOC, and elastic properties, are available from a large multiwell database, it is possible to extract reliable statistical relationships among properties. This paper documents a workflow to apply these relationships to other wells using wireline logs.