Year of Publication
Master of Science (MS)
Arts and Sciences
Earth and Environmental Sciences (Geology)
Dr. Michael M. McGlue
An integrated stratigraphic analysis of a ~350 ft drill core from Upton County (Texas) has revealed pervasive variability of several key siliciclastic and carbonate lithofacies in vertical section, where organic-rich siliceous mudrock beds alternate with aluminum-rich mudrocks and calcareous gravity flow deposits. Sediment chemistry, especially major and trace elements derived from x-ray fluorescence, captures this variability with high sensitivity. The high frequency chemostratigraphic variability appears to be cyclic, and it is interpreted to represent the first example of deep-water Late Pennsylvanian cyclothems for the Midland Basin. Positive trace metal (Mo, Cr) correlations to total organic carbon and gamma ray response in siliceous mudrocks, in conjunction with abundant pyrite, indicate bottom-water anoxia and possibly euxinia within the basin. The influence of glacial ice-sheets on the water level of the global ocean, in concert with local oceanographic gradients, regional tectonics, and tropical paleoclimate, constitute the primary controls on lithofacies and chemostratigraphy. The results of this study have implications for understanding the depositional history of the Midland Basin, as well as for identifying horizontal drilling zones for resource development.
Digital Object Identifier (DOI)
Baldwin, Patrick W., "LITHOSTRATIGRAPHIC AND GEOCHEMICAL CHARACTERIZATION OF THE UPPER PENNSYLVANIAN ‘WOLFCAMP D’ SHALE, MIDLAND BASIN (USA): IMPLICATIONS FOR PALEOENVIRONMENTS AND UNCONVENTIONAL PETROLEUM RESERVIORS" (2016). Theses and Dissertations--Earth and Environmental Sciences. 35.
Supplemental Figure 1. Whole Core XRF Analysis.pdf (1755 kB)
Supplemental Figure 2. Integrated Stratigraphy and Chemostratigraphy, Upton County Drill Core.pdf (1297 kB)
Supplemental Figure 3. Principle Component Analysis Upton County Drill Core.pdf (473 kB)