According to Wikipedia, the Barnett Shale was the most productive gas shale in the United States from 2002 to 2010. The Texas Railroad Commission designated the Barnett Shale in Fort Worth as the Newark, East Gas Field. The Barnett Shale underlies Tarrant County and at least sixteen other counties. The Barnett Shale also underlies my fictional town of Oak City.
In One Bark for Murder, I use geologic sample results, stratigraphy, and knowledge about oil and gas exploration, which includes the Barnett Shale, to help solve the murder cases in the story.