Holley Ellenburger Field, Nolan County, Texas

HOLLEY, DAVID G., Burger & Rhodes, Abilene, TX

The Holley Ellenburger field is located in northeast Nolan County, Texas, approximately 10 mi northeast of Sweetwater and 30 mi west of Abilene, Texas. The field is located just west of the Fort Chadbourne fault system, which is the source of the folding and faulting that formed hydrocarbon traps in this area. Nolan County has proved to be one of the most prolific Ellenburger producers in this area with over 42 million bbl produced.

The Holley Ellenburger field was discovered in 1986, with the reentry of a well drilled and abandoned in 1956. In those days, the common view was that if the Ellenburger did not produce from the first dolomite, then it would not be productive. A drill-stem test was taken in the first dolomite and showed no pressures. This was not the true Ellenburger, but a detrital zone on top of the true dolomite. Below this detrital zone was 36 ft of fractured porous dolomite that was not tested, but proved productive in the reentry.

Since its discovery, the Holley Ellenburger field has produced in excess of 500,000 bbl of oil from 13 wells. Pay thickness ranges from 5-50+ ft, with porosity types ranging from fractures to intergranular sandy dolomite. The field has approximately 200 ft of east dip and is bounded to the east by a large down-to-the-west fault, which is characteristic of Ellenburger fields in this area.

AAPG Search and Discovery Article #91011©1991 AAPG Southwest Section Meeting, Abilene, Texas, February 9-12, 1991 (2009)