Horizontal Drilling Potential of the Cane Creek Shale, Paradox Formation, Utah

MORGAN, CRAIG D., and THOMAS C. CHIDSEY, Utah Geological and Mineral Survey, Salt Lake City, UT

The Cane Creek shale of the Pennsylvanian Paradox Formation is a well-defined target for horizontal drilling. This unit is naturally fractured and consists of organic-rich marine shale with interbedded dolomitic siltstone and anhydrite. Six fields have produced oil from the Cane Creek shale in the Paradox basin fold-and-fault belt.

The regional structural trend is north-northwest with productive fractures occurring along the crest and flanks of both the larger and more subtle smaller anticlines. The Long Canyon, Cane Creek, Bartlett Flat, and Shafer Canyon fields are located on large anticlines, while Lion Mesa and Wilson Canyon fields produce from subtle structural noses.

The Cane Creek shale is similar to the highly productive Bakken Shale in the Williston basin. Both are (1) proven producers of high-gravity oil, (2) highly fractured organic-rich source rocks, (3) overpressured, (4) regionally extensive, and (5) solution-gas driven with little or no associated water.

Even though all production from the Cane Creek shale has been from conventional vertical wells, the Long Canyon 1 well has produced

nearly 1 million bbl of high-gravity, low-sulfur oil. Horizontal drilling may result in the development of new fields, enhance recovery in producing fields, and revive production in abandoned fields. In addition, several other regionally extensive organic-rich shale beds occur in the Paradox Formation. The Gothic and Chimney Rock shales for example, offer additional potential lying above the Cane Creek shale.

AAPG Search and Discovery Article #91010©1991 AAPG Rocky Mountain Section Meeting, Billings, Montana, July 28-31, 1991 (2009)