Petrophysical Analysis of the Green River Formation, Colorado-a Case Study in Oil Shale Formation Evaluation

摘要

The Green River formation in Southwestern Colorado is known as one of the world's richest oil shales and is the target for several oil companies' programs aimed at developing and evaluating technology to assess and develop the resource. Petrophysical evaluation of the potential liquid hydrocarbon yield is challenging due to the complex mineralogy that includes high and variable concentrations of minerals seldom encountered in conventional reservoirs. We present a case study of the evaluation of a comprehensive wireline and core data set that included natural, capture and inelastic gamma-ray spectroscopy, and NMR logs, and approximately twelve hundred feet of core-derived elemental and mineralogical analysis supplemented by Fischer Assays and RockEval pyrolysis measurements of the liquid hydrocarbon content.