1. Modeling Natural Fracture Networks in the Context of Flow Simulations: Teapot Dome, Wy
Thomas H. Wilson, Department of Geology and Geography, West Virginia University, Morgantown, WV 26506
The Pennsylvanian age Tensleep Formation produces oil from a tight, naturally fractured reservoir in which reservoir pressure is sustained by a water drive from an underlying aquifer. Tensleep wells have been producing oil for a half century, leaving about 60%of the original oil in place. The objectives of this study are to gain a detailed understanding of the fracture network controlling production from the Tensleep reservoir and to conduct flow simulations that will help design approaches to extract remaining reserves from the reservoir matrix. We completed characterization of the reservoir fracture network and bounding formations and development of a layered model for use in reservoir flow simulations. We were unable to obtain a history match in our flow simulations. A proposal was submitted to DOE NETL to continue this effort. The ACS PRF grant facilitated significant development and progress in this direction. The studies initiated under this grant are leading us closer to a better understanding of the nature of flow in the naturally fractured Tensleep reservoirs. Future work will help estimate recovery factors, CO2 storage potential and improve design of tertiary CO2 recovery operations.
Starting model used for flow simulations
Time structure on the Tensleep (left); 5-year cumulative production (right)
Ant track and ant-track grid (left); simulation grid and fracture network (right)
The credit for these images goes to my student, Valerie Smith.