The primary objective of this project is to assess and evaluate optimum strategies to drill economic wells in the structurally complex — but highly prospective — emerging unconventional Paradox oil play, in particular the Pennsylvanian Paradox Formation’s Cane Creek shale and adjacent clastic zones. A key component of this project is to fully characterize, quantify and interpret the geological, structural and geomechanical settings of the Paradox oil play to elucidate the relative factors that promote effective production. This strategy will include detailed facies analysis of core material, core-to-log petrophysical integration, advanced fracture analysis, innovative 3D seismic interpretation, and detailed basin modeling. The results of these analyses will inform a Development Strategy Plan that will include tailored drilling designs and/or stimulation strategies that will lead to maximized production from this play and other similar resources. In addition, the new strategic drilling and/or tactical stimulation approach(es) will be tested in at least one horizontal well in the Paradox Basin as part of this project.
University of Utah — Salt Lake City, UT 84112
Utah Geologic Survey — Salt Lake City, UT 84112
Brigham Young University — Provo, UT 84602
Rose Petroleum — Green River, UT 84525
Handwerger Petrophysics — Salt Lake City, UT 84112
Whidden et al. (2012) determined mean total undiscovered oil resources within the Cane Creek interval in the Paradox Basin at 215 million barrels and there is significant up-side potential in other unassessed adjacent clastic zones in this emerging play. To date, only 4% (8.9 million barrels) of the total Cane Creek resource has been produced from 37 wells, 26 of which are still active producers (including 21 horizontal wells). More than 96% of this historic production is from the central Cane Creek Unit (CCU). This project will use the knowledge gained from successful (and unsuccessful) drilling in the CCU to determine strategies to unlock production in areas to the north, Gunnison Valley Unit (GVU), and south, Par 5 Unit (P5U), making the Cane Creek a truly regional resource play. Moreover, this proposed project will leverage and extend the knowledge gained from recently completed DOE project Liquid-Rich Shale Potential of Utah’s Uinta and Paradox Basins: Reservoir Characterization and Development Optimization (DE-FE0010667; Vanden Berg et al., 2017).
This project will result in the full characterization, quantification, and interpretation of the geological, structural, and geomechanical settings of the northern Paradox oil play to elucidate the relative factors that promote effective production. To date, the GVU, CCU, and P5U have mostly been developed and managed by different companies in relative isolation from one another. This project aims to draw correlations between these related units through an industry cooperative arrangement. Within the larger regional context, additional insight can be gained resulting in improved production and management practices basin wide. This approach will allow for otherwise anecdotal experiences within the fields to be considered within the larger regional framework.
The project team successfully drilled a 9,745-foot-deep stratigraphic test well (State 16-2) in the Paradox Basin of Utah and extracted a greater-than-expected amount of whole core rock samples from the subsurface. The material will now be analyzed to better understand the region’s geology, especially the role of natural fractures, and identify optimum strategies to recover oil from the sizable Cane Creek resource play. Zephyr Energy and the Energy & Geoscience Institute at the University of Utah used the stratigraphic test well to obtain 113 feet of continuous whole core and 31 sidewall cores across multiple overlying reservoirs. The original project goal was to obtain 90 feet of continuous whole core. The stratigraphic well was also used to collect a set of geophysical logs for analysis. A dipole sonic log was also collected in a nearby lateral to supplement the available logs.
The conventional core analysis of the State 16-2 well is complete, and work continues on the specialty core analysis (MICP, relative permeability and geomechanics). Geologic data analysis and interpretation continues to aid in the development of a depositional model and a discrete fracture network (DFN) model for the Cane Creek. The project team is evaluating additional characterization options for new wells that will be drilled in the project area in calendar year 2022.
Comprehensive analyses of the cores and petrophysical logs is underway to better characterize and understand the geology and especially the role of geomechanics in the Cane Creek petroleum system, and by extension other potential reservoirs in the Paradox Basin and other basins in the western U.S. A primary objective is to exploit natural fractures as much as possible, to minimize environmental impacts of production from this and other similar unconventional plays. Work is ongoing to develop a depositional model and DFN model for the Cane Creek formation. The project is also evaluating additional characterization options for three wells that will be drilled in the project area in 2022.