Print this pageAAPG ANNUAL CONFERENCE AND EXHIBITION
Making the Next Giant Leap in Geosciences
April 10-13, 2011, Houston, Texas, USA
The Barnett Shale Oil Model of North Texas
(1) Republic Energy, Dallas, TX.
Initiation of the Barnett Shale gas 
play
in 1981 ushered in a new era of understanding of source rock resource plays. Over the years as industry's knowledge base increased many attempts were made to extend the shale play into the oil window. In the late 1980's, Mitchell made several unsuccessful attempts in Jack County followed by Oryx's 1991 failed attempt in their horizontal Grant #1 in Montague County.
In 2000, Dallas production Inc. drilled and completed their Swint #1 in the Barnett Shale as an oil well in Montague County and industry began to seriously consider the oil potential. However, the production data from the Swint#1 and unsuccessful attempts by industry to follow up on this producer only resulted in a short period of enthusiasm.
It was not until W. B. Osborne's successful recompletions and wells at St. Joe Ridge field in Southeast Montague County that industry really began to take notice. Mitchell Energy had internally proposed a Barnett Shale oil model in the late 90's, but due to low oil prices and preocccupation with the gas play, never tested the idea. There were many lines of evidence that suggested the existence of a commercial oil play and the geologic conditions by which it might be successful.
In 2008, EOG drew industry attention with their entry into a Barnett Shale oil play. Since that entry, EOG has adopted the name 'combo play' for good reason. Their early analysis had indicated commerciality would be dependent upon oil production, associated gas and the significant volumes of Natural Gas Liquids (NGL's). It was because of the liquids contribution that EOG almost immediately began construction of a 40 mmcfg/d natural gas processing plant.
With oil prices in excess of $60/BBL, the play has potential for being much more widespread than Mitchell's original model suggested. EOG's establishment of this combo play has created a new technological boom in the Barnett; however, like the gas play
it is not without risk.