Date of Graduation
Statler College of Engineering and Mineral Resources
Petroleum and Natural Gas Engineering
The application of horizontal drilling and hydraulic fracturing have made hydrocarbon production economically viable from the unconventional shale formations. Statistics show that currently, hydrocarbon production from shale formations play a major role in the overall production of hydrocarbon in the United States. However, the petrophysical characteristics of the shale which influence the hydrocarbon recovery and the optimization of hydraulic fracturing treatments have not been well established.;The characteristics of the unconventional formations, such as shale with ultra-low permeability, are often measured by unsteady-state techniques. The results of the unsteady state measurements, however, cannot be corrected for the pore and confining pressures and subsequently yield inconsistent values. In this research study, the porosity and the permeability of a Marcellus Shale core plug, obtained from a vertical well drilled at the Marcellus Shale Energy and Environment Laboratory (MSEEL) at a depth of 7547.03 feet, have been measured using the Precision Petrophysical Analysis Laboratory (PPAL). PPAL utilizes highly accurate pressure and pressure-differential transducers and is capable of measuring the permeability in a nano-Darcy range under steady-state conditions. The entire system is enclosed in a clear Lexan container to assure temperature stability. PPAL allows a measurement to be performed on the core plug under confining pressure up to 10,000 psi and the pore pressure up to 1,500 psi.;In this study, the impact of the pore pressure and stress on the permeability and porosity of the Marcellus Shale core plug were evaluated. The pore pressure and stress were found to have a significant impact on the measured permeability values. Furthermore, the permeability exhibited hysteresis with increasing and decreasing stress values. The porosity measurements were not significantly impacted by the stress. Moreover, it was observed that the absolute permeability varies non-linearly with the stress due to the presence of fractures that play the dominant role in permeability of the shale. The porosity exhibited a linear relation with stress because the fractures do not significantly contribute to the porosity. The permeability measurements with Nitrogen were impacted by adsorption effects to a small degree.
Elsaig, Mohamed, "Characterizations of the Marcellus Shale petrophysical properties" (2016). Graduate Theses, Dissertations, and Problem Reports. 5541.