Type of Thesis
With a shift to exploiting unconventional petroleum plays in the United States to support energy consumption, understanding the nanopore systems in those unconventional resources becomes important for future exploitation. The goal of this study is to characterize the pore systems of the Cretaceous Lincoln Limestone found in the Denver-Julesburg (DJ) Basin in order to test the hypothesis that lithologic variability has a control on pore characteristics and total porosity. The Lincoln Limestone represents a possible reservoir interval in close proximity to a source interval, the Hartland Shale, which directly overlies it, thus making it a potentially profitable future exploration target. Pore networks in the Lincoln were characterized using AR-milled rock surfaces run through a scanning electron microscope (SEM) for image capture, image analysis with Avizio 9 software, and mineralogical characterization by X-Ray fluorescence (XRF).
Seven samples were chosen for analysis from a single core taken from one well in the DJ basin. Five of the samples span the roughly 70-90 ft thick Lincoln Limestone and the other two come from right above and right below the Lincoln. The seven samples span the range of lithologic and porosity variability in the Lincoln Limestone. They have normalized volumes of carbonate that range from 6.0% to 70.6% (mostly as calcite); clay content ranges from 14.8% to 55.2%. The samples are thus marls (n=5), marly shale (n=1) and shale (n=1). Total organic carbon (TOC) contents range from 1.5% to 7.8% and porosity ranges from 5.0% to 10.4%.
Chase, Brandon, "Variability of Nanopore Systems In The Lincoln Limestone, Denver-Julesburg Basin, Colorado, USA" (2016). Undergraduate Honors Theses. 1113.