X-Ray Fluorescence Applications in Mudrock Characterization: Investigations into Middle Devonian Stratigraphy, Appalachian Basin, USA
Date of Graduation
Eberly College of Arts and Sciences
Geology and Geography
Mudrocks are characterized by nanometer-scale pore sizes and nano-darcy permeability, which plays a significant role in hydrocarbon flow during production. Resulting from these characteristics, mudrocks were exclusively considered a source rock, which charged overlying, more porous mediums. Hydraulic fracturing, a technology used to create artificial fractures to liberate hydrocarbons from the reservoir, enabled natural gas to be produced from mudrock reservoirs economically. Over the last fifteen years, this technology motivated research efforts to understand reservoir characteristics of mudrock. These investigations significantly improved our knowledge of mudrock systems, but have also highlighted key areas that are undeveloped and/or where conflicting hypotheses exist. Utilizing wave-dispersive X-ray fluorescence (XRF) and high-resolution handheld energy-dispersive X-ray fluorescence (hhEDXRF) datasets collected from seven middle Devonian core throughout the Appalachian basin, this dissertation focuses on three areas of mudrock research: (1) development of mudrock calibrations to increase the analytical quality of hhEDXRF datasets, (2) investigation into the relationship between chemical composition of the host rock and natural fracture presence, and (3) assessment of the relationship between paleo-depositional conditions and organic carbon enrichment. This research indicates that lithology-specific calibrations significantly increase the analytical quality of hhEDXRF datasets, natural fractures preferential concentrate in zones of similar composition in a predictable manner, and an interplay of limited dilution and a robust anoxia-productivity feedback mechanism controlled organic carbon enrichment within middle Devonian mudrock of the Appalachian basin.
Martin, Keithan Garrett, "X-Ray Fluorescence Applications in Mudrock Characterization: Investigations into Middle Devonian Stratigraphy, Appalachian Basin, USA" (2019). Graduate Theses, Dissertations, and Problem Reports. 7462.