Energy Policy Act of 2005 (Ultra-deepwater and Unconventional Resources Program)
Cretaceous Mancos Shale Uinta Basin, Utah: Resource Potential and Best Practices for an Emerging Shale Gas Play
Utah Geological Survey, Salt Lake City, Utah
University of Utah
Halliburton Energy Services
Existing gas production in the Uinta Basin could be greatly enhanced by the addition of gas reserves in the Cretaceous Mancos Shale. The Mancos Shale is an emerging shale gas play, but both the geologic and engineering insights are immature, presenting the industry with poorly constrained exploration and development risks. As with many emerging shale gas resources, the resource has not been fully characterized, reliable estimates of gas in place are not available, and production potential is poorly constrained. Specifically, among the thousands of feet of strata the optimum intervals and best exploitation strategies are unknown. To quantify the plays’ financial risks, accurate geologic and geophysical characterization must be integrated with reservoir specific engineering practices. To accomplish this, the project will:
- Characterize the geology (sedimentology, stratigraphy, organic, stable isotope, and inorganic geochemistry, natural fracture analysis, and geophysical and 3-D seismic analysis) of the Mancos Shale in the Uinta Basin in order to identify premium target zones, and determine the resource potential.
- Define the geologic parameters that determine various geomechanical properties (i.e. brittle-ness, “fracability”). These relationships are currently poorly understood. Use defined relevant geologic parameters to predict regions of brittleness (“fracability”) and Mancos shale gas prospectivity, from an engineering perspective.
- Establish best drilling, completion, and production techniques for specific targeted intervals based on their rock properties.
Geologic and engineering evaluation will use public and proprietary datasets; well logs, core, well cuttings, geochemical data, 3-D seismic information and production data. This project will produce a GIS-based integrated geologic characterization of the Mancos Shale along with drilling, completion, and stimulation method recommendations. The proposed investigation will quantify and potentially lower the economic risk of exploration and development in the Mancos Shale Gas play, encouraging larger-scale, commercial production.
To provide integration of geologic and engineering disciplines, the project team includes sedimentary geology, geochemistry, geomechanics, production engineering, petrophysical log evaluation, seismic evaluation, reservoir simulation, and hydraulic fracturing specialists. Project team members have been assembled from the Utah Geological Survey, the University of Utah’s Energy & Geoscience Institute, Geology and Geophysics Department, Chemical Engineering Department, and Halliburton Energy Services. Questar Exploration & Production, Gasco Energy, Wind River Resources and Pioneer Natural Resources, will participate in the project, by donating data. Many other Uinta Basin gas producers will participate as Advisory Board members, many of whom may contribute data as the project progresses but are unable to commit assets to the project at this time.
Principal Investigator: Craig D. Morgan