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Realizations

In statistics, a realization is an observed value of a random variable (Gubner 2006). In mathematical geology, the most important realizations are those in the form of maps of spatially correlated regionalized variables.Spatial description of random variables within complex domains and making certain decisions about those require complete knowledge of the attribute of interest at each point in spa
Authors
C. Özgen Karacan

A comprehensive statewide spatiotemporal stream assessment of per- and polyfluoroalkyl substances (PFAS) in an agricultural region of the United States

Public concern regarding per- and polyfluoroalkyl substances (PFAS) has grown substantially in recent years. In addition, research has documented multiple potential agriculture-related release pathways for PFAS (e.g., biosolids and livestock manure). Nevertheless, little research on the environmental prevalence of PFAS has been conducted in agricultural regions of the United States. To fill this g

Authors
Dana W. Kolpin, Laura E. Hubbard, D.M. Cwiertny, Shannon M. Meppelink, D.A. Thompson, James L. Gray

Hydrous pyrolysis of New Albany Shale: A study examining maturation changes and porosity development

The characterization of nanoscale organic structures has improved our understanding of porosity development within source-rock reservoirs, but research linking organic porosity evolution to thermal maturity has generated conflicting results. To better understand this connection, an immature (0.25% solid bitumen reflectance; BRo) sample of the New Albany Shale was used in four isothermal hydrous py
Authors
Brett J. Valentine, Paul C. Hackley, Javin J. Hatcherian

DAS 3DVSP survey at Stratigraphic Test Well (Hydrate-01)

This proceeding outlines the acquisition, processing, and fault interpretation of the largest known onshore distributed acoustic sensing (DAS) 3D vertical seismic profile (VSP) survey. This survey was carried out to detect the distribution of faults near the gas hydrate research well (Stratigraphic Test Well: Hydrate-01) on the North Slope of Alaska within the Prudhoe Bay Unit (PBU). The data were
Authors
Akira Fujimoto, Teck Kean Lim, Machiko Tamaki, Kyojiro Kawaguchi, Toshiaki Kobayashi, Seth S. Haines, Timothy Collett, Ray Boswell

Quantitative modeling of secondary migration: Understanding the origin of natural gas charge of the Haynesville Formation in the Sabine Uplift area of Louisiana and Texas

The Upper Jurassic (Kimmeridgian) mudstones of the Haynesville Formation in the Sabine Uplift, Louisiana and Texas, are widely considered to be a self-sourced natural gas reservoir; however, additional sources of gas may have charged the mudstones in the Louisiana portion of the uplift. Secondary migration of hydrocarbons into the Sabine Uplift from downdip, gas-generating Jurassic source rocks in
Authors
Lauri A. Burke

Machine learning can assign geologic basin to produced water samples using major ion geochemistry

Understanding the geochemistry of waters produced during petroleum extraction is essential to informing the best treatment and reuse options, which can potentially be optimized for a given geologic basin. Here, we used the US Geological Survey’s National Produced Waters Geochemical Database (PWGD) to determine if major ion chemistry could be used to classify accurately a produced water sample to a
Authors
Jenna L. Shelton, Aaron M. Jubb, Samuel Saxe, Emil D. Attanasi, Alexei Milkov, Mark A Engle, Philip A. Freeman, Christopher Shaffer, Madalyn S. Blondes

Compositional evolution of organic matter in Boquillas Shale across a thermal gradient at the single particle level

The molecular composition of petroliferous organic matter and its compositional evolution throughout thermal maturation provides insight for understanding petroleum generation. This information is critical for understanding hydrocarbon resources in unconventional reservoirs, as source rock organic matter is highly dispersed, in contact with the surrounding mineral matrix, and may occur as multiple
Authors
Justin E. Birdwell, Aaron M. Jubb, Paul C. Hackley, Javin J. Hatcherian

National assessment of helium resources within known natural gas reservoirs

Using available data, the U.S. Geological Survey estimated that 306 billion cubic feet of recoverable helium is presently within the known geologic natural gas reservoirs of the United States.
Authors
Sean T. Brennan, Jennifer L. Rivera, Brian A. Varela, Andy J. Park

Frequency distribution

Given a numerical dataset, a frequency distribution is a summary displaying fluctuations of an attribute within the range of values. In contrast to an analytical probability distribution, a frequency distribution always deals with empirically observed values (Everitt and Skondall 2010). In general, the larger the number of values, the more useful is the frequency distribution relative to listing a
Authors
Ricardo A. Olea

Revisiting the declustering of spatial data with preferential sampling

Preferential sampling is a form of data collection that may significantly distort the histogram and the semivariogram of spatially correlated data. Typical situations are a higher sampling density at high-valued areas favorable for mining, and highly contaminated areas in need of environmental remediation. Multiple statistical procedures are devoted to obtaining representative statistics, whose ma
Authors
Ricardo A. Olea

Geochemical and mineralogical properties of Boquillas Shale geochemical reference material ShBOQ-1

The ShBOQ-1 geochemical reference material is relevant to studies of the organic geochemistry and mineralogy of petroleum source rocks containing high concentrations of carbonate minerals and organic sulfur-rich, oil-prone marine organic matter. ShBOQ-1 is geochemically and mineralogically similar to the lower part of the Upper Cretaceous Eagle Ford Shale.
Authors
Justin E. Birdwell, Stephen A. Wilson