Identifier

etd-07292012-174652

Degree

Master of Science (MS)

Department

Geology and Geophysics

Document Type

Thesis

Abstract

New drilling technology has led to a revival of drilling in mature petroleum basins such as the Haynesville Formation in east Texas and north Louisiana. In north Louisiana, the Upper Jurassic (Kimmeridgian) aged Haynesville shale has a basinward SW dip and is located at depths ranging from around 10,500 ft to the northeast and 14,000 ft to the southwest with local minimums at the Sabine and Monroe Uplifts. Formation thickness ranges from 100 to 400 feet. Prolific natural gas production is attributed to relatively high average porosity (8 to 14%) and a high geopressure gradient > 0.9 psi/ft. (Wang and Hammes, 2010). Using subsurface data, 1-dimensional and 2-dimensional models across the North Louisiana Salt Basin were created to estimate the thermal, pressure, and fluid flow histories of the Haynesville Shale. Disequilibrium compaction from rapid sedimentation in the low permeability (nanodarcy) Haynesville Shale coupled with hydrocarbon generation has resulted in high pore pressures ranging from about 7000 psi to 12000 psi. Hydrocarbon generation resulted in a maximum pressure increase of 500 psi at 88 Ma; however models created with and without hydrocarbon generation produced nearly identical results for present day pore pressure indicating that disequilibrium compaction is the most significant mechanism in generating overpressure. Updip fluid migration to the Sabine Uplift within the Haynesville Shale and underlying Smackover Limestone has resulted in abnormally high fluid pressures on the Sabine Uplift. 1D and 2D models did not calculate pressures in excess of the fracture gradient; however natural fractures likely aided in lateral fluid migration within the Haynesville Shale. A 3D model that incorporates fluid migration from the entire basin and the East Texas Salt Basin is needed to accurately estimate the pressure history of the Haynesville Shale.

Date

2012

Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Nunn, Jeffrey

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