|Liquid-Rich Shale Potential of Utah’s Uinta and Paradox Basins: Reservoir Characterization and Development Optimization
||Last Reviewed 12/23/2013
The overall goal of the project is to provide reservoir-specific geological and engineering analyses of the emerging Green River Formation (GRF) tight oil plays in the Uinta Basin, and the established, yet understudied Cane Creek shale (and possibly other shale units) of the Paradox Formation in the Paradox Basin.
Utah Geological Survey, Salt Lake City, Utah
Energy and Geoscience Institute, University of Utah, Salt Lake City, Utah
Eby Petrology and Consulting, Denver, Colorado
Uinta Basin Petroleum Companies: Anadarko Petroleum Corp., Berry Petroleum Co., Bill Barrett Corp., Newfield Exploration Co., QEP Resources, Inc.
Paradox Basin Petroleum Companies: Anadarko Petroleum Corp., Fidelity Exploration & Production, SM Energy Co., Southwestern Energy, Patara Oil & Gas LLC, Stone Energy Corp.
The high price of crude oil, coupled with lower natural gas prices, have generated renewed interest in exploration and development of liquid hydrocarbon reserves. Petroleum companies are following the success of the recent shale gas boom and employing many of the same well completion techniques to explore for liquid petroleum in shale formations. In fact, many shale formations targeted for natural gas include areas in which the shale is more prone to liquid production. In Utah, organic-rich shales in the Uinta and Paradox Basins have been a source of significant hydrocarbon generation, with companies traditionally targeting the interbedded sands or carbonates for their conventional resource recovery. Operators in these basins are exploiting advances in horizontal drilling and hydraulic fracturing techniques to explore the petroleum production potential of the shale units themselves.
The GRF in the Uinta Basin has been studied for over 50 years since hydrocarbons were first discovered. However, those studies focused on the many conventional sandstone reservoirs currently producing oil and gas. Very little information exists about the more unconventional crude oil production potential of thinner shale/carbonate units such as the Uteland Butte member, Black Shale facies, deep Mahogany zone, and other deep Parachute Creek Member high-organic units. Some operators have recently conducted geochemical and geomechanical characterization, natural fracture analysis, and thickness mapping in these prospective GRF units, but this work has been completed for only limited geographic areas, usually where the operators have leases, and the results are often confidential.
The specific objectives of the project’s research are to (1) characterize geologic, geochemical, and geomechanical rock properties of target zones in the two designated basins by compiling data and analyzing available cores, cuttings, and well logs; (2) describe outcrop reservoir analogs of GRF plays (Cane Creek shale is not exposed) and compare them to subsurface data; (3) map major regional trends for targeted intervals and identify “sweet spots” that have the greatest oil potential; (4) reduce exploration costs and drilling risks, especially in environmentally sensitive areas; (5) improve drilling and fracturing effectiveness by determining optimal well completion design; and (6) reduce field development costs, maximize oil recovery, and increase reserves. The project will therefore develop and make available geologic and engineering analyses, techniques, and methods for exploration and production from the GRF tight oil zones and the Paradox Formation shales where operations encounter technical, economic, and environmental challenges.
The detailed reservoir characterization and rock mechanics analyses will provide the basis for identification of “sweet spots” and improve well completion strategies for these undeveloped and under-developed reservoirs. The project will provide (1) improved and detailed reservoir characterization of the GRF tight oil plays in the Uinta Basin and the Paradox Formation shale oil plays (in particular the Cane Creek shale) in the Paradox Basin, targeting specific, brittle, high potential intervals, and (2) improved methods for identification of “sweet spots” using methods such as epifluorescence analysis of regional well core and cuttings. The reservoir characterization and analysis will be based on newly acquired and donated core, well logs, and well cuttings, which will be used to improve well placement and establish a relationship between natural fractures and productivity; thus reducing the number of wells and the environmental impact of drilling. Analysis of in situ stress, using geophysical and other geomechanical data, will be used to improve hydraulic fracture design for development of new fields or expanding established fields. The project will provide operators with the information they need to reduce exploration and development costs and drilling risks while maximizing oil recovery and increasing reserves.
Accomplishments (most recent listed first)
One of the main goals of Budget Period 1 was to locate and describe all available cores from the two primary target intervals in the Uinta and Paradox Basins. Project team members located and described in detail ten lower GRF cores (mostly from the Uteland Butte Member) and collected all associated data. This data will help project members to develop a regional geologic picture of the Uteland Butte play and determine were data gaps exist. Project team members also described one core from the Cane Creek shale in the Paradox Formation, collecting high-resolution XRF data and performing select RockEval analyses.
Several additional Cane Creek shale cores are currently being acquired for the project. Several technology transfer opportunities were undertaken in Budget Period 1, including the presentation of a Uteland Butte core poster at the AAPG Annual meeting in Pittsburgh, PA, in May 2013; the presentation of a Cane Creek core poster and oral presentation at the AAPG-RMS meeting in Salt Lake City, UT, in September 2013; as well as submittal of an abstract on the Cane Creek shale to the AAPG Annual meeting to be held in Houston, TX, in April 2014. These presentations and abstracts are (or soon will be) available on the UGS project website.
An east-west cross section through the central Uinta Basin, which includes many of the wells with Uteland Butte core was drafted. The cross section was displayed on the poster presented at the AAPG conference in Pittsburgh and then uploaded to the project website.
Technology transfer that took place in January 2013 included a presentations to (1) the UGS board and (2) at the annual Utah Governor’s Energy Summit and (3) at the quarterly Uinta Basin Oil and Gas Collaborative Group Meeting in Vernal, UT, which was attended by representatives from several state and federal agencies and oil and gas companies, and the general public.
Current Status (December 2013)
In order to accomplish the Task 6 goals, a geomechanical testing program is now underway to help determine the reservoir’s mechanical properties and help optimize well completion strategies. Two new Masters level graduate students at the University of Utah will work on the geomechanical aspects of this project as part of their thesis research.
Several cores from the target intervals in the Uinta Basin have been found and described, but only one Cane Creek core has been analyzed by the project team. Over the past few months, the Project team has worked to locate several additional Cane Creek cores, especially from the most prospective production areas in the northern Paradox Basin. These new cores should be available for study soon and will be vital to a complete understanding of the Cane Creek play.
Members of the research team have begun compiling lists of available cores and cuttings and conducting literature reviews. A bibliography of published stratigraphic, petrologic, and geochemical analyses of the Uinta and Paradox Basins will be compiled and published to the project website (http://geology.utah.gov/emp/shale_oil[external site]).
Project Start: October 1, 2012
Project End: September 30, 2015
DOE Contribution: $737,390
Performer Contribution, including subcontractor cost-share: $184,348
NETL – Chandra Nautiyal (Chandra.Nautiyal@netl.doe.gov or 281-494-2488)
Utah Geological Survey - Michael Vanden Berg (email@example.com or 801-538-5419)
Quarterly Research Progress Report [PDF-1.68MB] October - December, 2013
Quarterly Research Progress Report [PDF-1.81MB] July - September, 2013