The Barnett Shale is thermally mature for hydrocarbon generation over most of its area. Barnett source rock is presently in the oil-generation window along the north and west parts of the province, and in the gas window on the east half of the Barnett-Paleozoic TPS. Expulsion of high-quality oil from the Barnett was episodic and began at low (Ro = 0.6%) thermal maturity. Thirty-two oils from Wise and Jack Counties were analyzed to determine the characteristics of the generating source rock. API gravity and sulfur content were integrated with high-resolution gas chromatography (GC) and Gas chromatography-mass spectrometry (GCMS) analyses. The API gravity of the oils ranges from 35° to 62° and sulfur contents are low (<0.2%), which is characteristic of high thermal maturity oils. Biomarkers from GCMS analyses show oils were sourced from marine shale, based on sterane distribution and the presence of diasteranes. Carbon isotopic analyses of saturated and aromatic hydrocarbon fractions support hydrocarbon generation from a single-source unit. In the main gas-producing area of fractured Barnett Shale, the gas generation window is along a trend sub-parallel to the Ouchita thrust front. Jarvie (2001) reported the British Thermal Unit (BTU) content of Barnett gas is directly proportional to Ro levels.
Read more about this topic: Bend Arch–Fort Worth Basin
Famous quotes containing the word generation:
“I dont want to be an alarmist, but I think that the Younger Generation is up to something.... I base my apprehension on nothing more definite than the fact that they are always coming in and going out of the house, without any apparent reason.”
—Robert Benchley (18891945)