Publications

No abstract available.

The hydrocarbon remnants of biologically diagnostic lipids inform our understanding of Earth’s early ecosystems, particularly where morphological vestiges of biology are absent or ambiguous. Yet both the analysis and interpretation of ancient biomarkers require scrutinous approaches. Here, we describe the status quo of Precambrian biomarker geochemistry with four examples that highlight current ch

A previously completed mineral resources assessment of the Texas Coastal Plain indicated the potential for the future discovery of uranium resources. Geoenvironmental assessments that include the hydrogeologic framework can be used as a tool to understand the potential effects of mining operations. The hydrogeologic framework for this study focused on the composite hydrogeologic unit of the tract

In-situ recovery (ISR) has been the only technique used to extract uranium from sandstone-hosted uranium deposits in the Pliocene Goliad Sand in the Texas Coastal Plain. Water plays a crucial role throughout the ISR lifecycle of production and groundwater restoration yet neither the water use nor other environmental footprints have been well documented. The goal of this study is to examine histori

Sequence stratigraphy provides a unifying framework for integrating diverse observations to interpret sedimentary basin evolution; however, key time assumptions about stratigraphic elements spanning hundreds of kilometers are rarely quantified. We integrate new detrital zircon U-Pb (DZ) dates from 28 samples with seismic mapping to establish a chronostratigraphic framework across 800 km and ~20 m.

Gas hydrates are found in significant quantities on the North Slope of Alaska in subpermafrost sand units and intermixed in lower portions of permafrost within the hydrate stability window. While conventional surface seismic data and established imaging methods can indicate the presence of gas hydrate reservoirs, producing high-resolution images of (seismically) thin layers remains challenging due

The National Energy Technology Laboratory, the Japan Oil, Gas and Metals National Corporation, and the U.S. Geological Survey are leading an effort to conduct an extended gas hydrate production test in northern Alaska. The proposed production test required the drilling of an initial stratigraphic test well (STW) to confirm the geologic conditions of the proposed test site. This well was completed

No abstract available.

The Coles Hill uranium deposit with an indicated resource of about 130 million lbs. of U3O8 is the largest unmined uranium deposit in the United States. The deposit is hosted in the Taconian (approximately 480 – 450 Ma) Martinsville igneous complex, which consists of the Ordovician Leatherwood Granite (granodiorite) and Silurian Rich Acres Formation (diorite). The host rock was metamorphosed to or

No abstract available.

Urban development is a well-known stressor for stream ecosystems, presenting a challenge to managers tasked with mitigating its effects. For the past 20 y, streamflow, water quality, geomorphology, and benthic communities were monitored in 5 watersheds in Montgomery County, Maryland, USA. This study presents a synthesis of multiple studies of monitoring efforts in the study area and new analysis o

The Hydrate-01 Stratigraphic Test Well was drilled at the Kuparuk 7-11-12 site on the Alaska North Slope in December 2018. Sonic log data provide compressional (P) and shear (S) slowness from which we determine gas hydrate saturation (Sgh) estimates using effective medium theory. The sonic Sgh estimates compare favorably with Sgh estimated from resistivity and nuclear magnetic resonance (NMR) logs