APPENDIX B - Depositional heterogeneity and fluid flow modeling of the oil shale interval of the upper Green River Formation, eastern Uinta Basin, Utah - Final Project Report - Reporting period: June 21, 2006 to October 21, 2009

In this project, a detailed geological analysis was performed followed by a reservoir modeling exercise. For the geological analysis, ~300 m of cores were correlated to gamma and density logs in well P4 in the lower to middle Eocene (49.5-48.0 million years ago (Ma)), upper Green River Formation of the eastern Uinta Basin, Uintah County, Utah. In well P4, three distinct facies associations were identified that represent three phases of deposition linked to the hydrologic evolution of Lake Uinta: 1) an overfilled, periodically holomictic lake system with deposition of primarily clastic mudstones, followed by 2) a balanced-filled, uniformly meromictic lake system with deposition of primarily calcareous and dolomitic mudstones, followed by 3) an underfilled, evaporative lake system with nahcolite precipitation. The richest oil shale zones were deposited during the second depositional phase. While the studied interval is popularly known as oil "shale", this bed-by-bed investigation revealed that lithologically, thus chemically, the interval is quite heterogeneous. This complexity has significant impact on modeling strategies for oil shale exploitation.