Petrophysical Analysis of Eagle Ford Shale: A Preliminary Assessment
Discoveries of oil and gas windows of the Eagle Ford Shale Formation in Texas, have led to a surge of over 4000 operational permits since 2010. Despite advancements in shale analysis, the proprietary natures of core samples have greatly prevented a large amount of data from public exposure. This study focuses on analyzing the petrophysical properties of distinct core samples from the Eagle Ford Shale formation, and then determining whether those properties vary with respect to geography and geological environment. Utilizing a BET Nitrogen Gas adsorption instrument, pore size distribution and adsorption/desorption data are able to provide porosity and pore volume analysis. Scanning Electron Microscope (SEM) imaging of pore structures provides reinforcing analysis to the permeability data from the Probe Permeameter instrument, in addition to the support from the X-Ray Diffraction (XRD) mineralogical and chemical analysis. Preliminary observations found correlations between porosity and pore size distribution. The pore size distribution measurements suggest relationships between pore connectivity and porosity for each core sample. The permeability data were inconclusive due to lack of instrument sensitivity. Future work with mercury injection analysis is required in order to obtain a greater spectrum of measurements that are limited by the nitrogen gas adsorption method. Further analyses of the mineralogical and physical characteristics are essential to assert any relationship with depth and geography. Such addition measurements are necessary in order to associate observations with shale hydrocarbon window characteristics. In addition, the collected Eagle Ford measurements and analysis will be compared to petrophysical data from Utica and Point Pleasant shale data. This compare and contrast of varying unconventional plays will help strive towards understanding unconventional plays in Academia.
AAPG Datapages/Search and Discovery Article #90195 © 2014 Eastern Section Meeting, London, Ontario, Canada, September 27-30, 2014