Gas production from the Barnett Shale has led to an explosion in drilling activity within the Ft Worth Basin since the year 2001 and an increased level of evaluating black shales as unconventional hydrocarbon sources. A need for understanding the Barnett Shale as a source/reservoir system has led us to examine the various rock types that comprise this economic giant in North Central Texas. Along the southern margin of the Ft Worth basin and northern flank of the Llano Uplift a series of Barnett outcrops occur. Petrographic and geochemistry data from these exposures enable us to evaluate the Barnett in an immature thermal setting with most of the primary organic and mineral constituents preserved. Within the axis of the Ft Worth Basin, where the Barnett is most productive, the formation is thicker and thermally mature with much of the organic matter already well into the gas window. Conventional core and drill cuttings have been analyzed from the subsurface over a multi county area and similar lithofacies occur repeatedly within the reservoir/source system. Organic-rich shales, silica rich shales, micro-laminated carbonates and pelletal facies are common throughout the Barnett. Understanding the vertical and lateral distribution of the various lithofacies should enable operators to high grade their exploration acreage and better understand the well performances.
This presentation has been composed by Bo Henk and Jim Hickey and will be presented by Bo Henk adapted for an engineering audience.