Physical Sciences and Mathematics Commons^™

Predictive Modeling Of Cave Entrance Locations: Relationships Between Surface And Subsurface Morphology, William Blitch, Adia R. Sovie, Benjamin Tobin

Faculty, Staff, and Affiliated Publications--KGS

Cave entrances directly connect the surface and subsurface geomorphology in karst landscapes. Understanding the spatial distribution of these features can help identify areas on the landscape that are critical to flow in the karst groundwater system. Sinkholes and springs are major locations of inflow and outflow from the groundwater system, respectively, however not all sinkholes and springs are equally connected to the main conduit system.

Predicting where on the landscape zones of high connectivity exist is a challenge because cave entrances are difficult to detect and imperfectly documented. Wildlife research has a similar issue of understanding the complexities of where …

Automatic Segmentation Of Sinkholes Using A Convolutional Neural Network, Muhammad Usman Rafique, Junfeng Zhu, Nathan Jacobs

Faculty, Staff, and Affiliated Publications--KGS

Sinkholes are the most abundant surface features in karst areas worldwide. Understanding sinkhole occurrences and characteristics is critical for studying karst aquifers and mitigating sinkhole-related hazards. Most sinkholes appear on the land surface as depressions or cover collapses and are commonly mapped from elevation data, such as digital elevation models (DEMs). Existing methods for identifying sinkholes from DEMs often require two steps: locating surface depressions and separating sinkholes from non-sinkhole depressions. In this study, we explored deep learning to directly identify sinkholes from DEM data and aerial imagery. A key contribution of our study is an evaluation of various ways …

Geospatial Applications Of Cave Resource Data To Better Understand Epikarst And Unsaturated Zone Groundwater Flow Path Development, Sierra M. Heimel, Benjamin W. Tobin

Faculty, Staff, and Affiliated Publications--KGS

The unsaturated zone is a critical component of karstic groundwater systems and is shown to provide substantial storage capacities. Understanding the spatial patterns and controls on flow path activation is often a challenge. Previous research focused on remotely sensed data or inferential analyses to quantify these patterns. Here, we use two cave systems—one in Arizona, USA and a second in Kentucky, USA—to show the value of the cave survey and inventory data in the direct observation of speleogenesis and unsaturated zone processes. Using geospatial statistical analyses, we show that passage size varies with distance from some faults, indicating that these …

Analysis Of Rock Varnish From The Mojave Desert By Handheld Laser-Induced Breakdown Spectroscopy, Russell S. Harmon, Daria Khashchevskaya, Michelle Morency, Lewis A. Owen, Morgan Jennings, Jeffrey R. Knott, Jason M. Dortch

Faculty, Staff, and Affiliated Publications--KGS

Laser-induced breakdown spectroscopy (LIBS) is a form of optical emission spectroscopy that can be used for the rapid analysis of geological materials in the field under ambient environmental conditions. We describe here the innovative use of handheld LIBS for the in situ analysis of rock varnish. This thinly laminated and compositionally complex veneer forms slowly over time on rock surfaces in dryland regions and is particularly abundant across the Mojave Desert climatic region of east-central California (USA). Following the depth profiling examination of a varnished clast from colluvial gravel in Death Valley in the laboratory, our in situ analysis of …

Coal Energy And Environmental Impacts: Introduction, Luis F. O. Silva, Amy L. Wolfe

Faculty, Staff, and Affiliated Publications--KGS

No abstract provided.

The Future Environmental And Health Impacts Of Coal, Robert B. Finkelman, Amy L. Wolfe, Michael S. Hendryx

Faculty, Staff, and Affiliated Publications--KGS

In the United States, coal consumption in the last 12 years has declined from 1,045,140 million short tons in 2007 to 539,420 million short tons in 2019, a decrease of almost 50%. During that period the number of electric power coal generators has declined from 1,470 to 738 accounting for 21% of capacity. An even more dramatic decrease in coal use has occurred in Western Europe. This significant reduction in coal use and the concomitant closure of coal mines and coal-burning power plants will result in substantially cleaner air, reductions in respiratory problems such as asthma, less heart disease, fewer …

A Geologically Based Indoor-Radon Potential Map Of Kentucky, William C. Haneberg, Amanda T. Wiggins, Douglas C. Curl, Stephen F. Greb, William M. Andrews Jr., Kathy Rademacher, Mary Kay Rayens, Ellen J. Hahn

Faculty, Staff, and Affiliated Publications--KGS

We combined 71,930 short-term (median duration 4 days) home radon test results with 1:24,000-scale bedrock geologic map coverage of Kentucky to produce a statewide geologically based indoor-radon potential map. The test results were positively skewed with a mean of 266 Bq/m³, median of 122 Bq/m³, and 75th percentile of 289 Bq/m³. We identified 106 formations with ≥10 test results. Analysis of results from 20 predominantly monolithologic formations showed indoor-radon concentrations to be positively skewed on a formation-by-formation basis, with a proportional relationship between sample means and standard deviations. Limestone (median 170 Bq/m³) …

Pleistocene/Holocene Cave Fossils From Grand Canyon National Park: Ice Age (Pleistocene) Flora, Fauna, Environments, And Climate Of The Grand Canyon, Arizona, Jim I. Mead, Justin S. Tweet, Vincent L. Santucci, Benjamin Tobin, Carol L. Chambers, Shawn C. Thomas, Mary C. Carpenter

Faculty, Staff, and Affiliated Publications--KGS

The Colorado Plateau is a distinct physiographic province in western North America covering an area of roughly 337,000 km² (130,115 mi²) across parts of Arizona, Colorado, New Mexico, and Utah. Elevations range from about 360 m (1,180 ft) in the overall Grand Canyon (GC; which includes the Grand Canyon National Park, GRCA) river corridor to an average at the eastern South Rim of 2,072 m (6,800 ft) to 3,850 m (12,630 ft) on the nearby San Francisco Peaks at Flagstaff, Arizona, with an average elevation of 1,525 m (5,000 ft). The Colorado River of Grand Canyon is …

Spatially Heterogeneous Post-Caledonian Burial And Exhumation Across The Scottish Highlands, Michelle L. Fame, James A. Spotila, Lewis A. Owen, Jason M. Dortch, David L. Shuster

Faculty, Staff, and Affiliated Publications--KGS

The postassembly, postrift evolution of passive margins is an essential element of global continental tectonics. Thermal and exhumational histories of passive margins are commonly attributed to a number of drivers, including uplift and erosional retreat of a rift-flank escarpment, intraplate fault reactivation, mantle-driven uplift, and erosional disequilibrium, yet in many cases, a specific factor may appear to dominate the history of a given passive margin. Here, we investigate the complex evolution of passive margins by quantifying exhumation patterns in western Scotland. We build upon the well-studied thermal evolution of the Scottish North Atlantic passive margin to test the importance of …

Assessment Of Thermal Maturity Trends In Devonian–Mississippian Source Rocks Using Raman Spectroscopy: Limitations Of Peak-Fitting Method, Jason S. Lupoi, Luke P. Fritz, Thomas M. Parris, Paul C. Hackley, Logan Solotky, Courtland F. Eble, Steve Schlaegle

Faculty, Staff, and Affiliated Publications--KGS

The thermal maturity of shale is often measured by vitrinite reflectance (VRo). VRo measurements for the Devonian–Mississippian black shale source rocks evaluated herein predicted thermal immaturity in areas where associated reservoir rocks are oil-producing. This limitation of the VRo method led to the current evaluation of Raman spectroscopy as a suitable alternative for developing correlations between thermal maturity and Raman spectra. In this study, Raman spectra of Devonian–Mississippian black shale source rocks were regressed against measured VRo or sample-depth. Attempts were made to develop quantitative correlations of thermal maturity. Using sample-depth as a proxy for thermal maturity is not without …

The Strain Seismograms Of P- And S-Waves Of A Local Event Recorded By Four-Gauge Borehole Strainmeter, Zehua Qui, Shunliang Chi, Zhenming Wang, Seth Carpenter, Lei Tang, Yanping Guo, Guang Yang

Faculty, Staff, and Affiliated Publications--KGS

At a sampling rate of 100 samples per second, the YRY-4 four-gauge borehole strainmeters (FGBS) are capable of recording transient strains caused by seismic waves such as P and S waves or strain seismograms. At such a high sampling rate, data from the YRY-4 strainmeters demonstrate fairly satisfactory self-consistency. The strain tensor seismograms demonstrate the senses of motion of P waves, that is, the type of seismic wave travels in the direction of the maximum normal strain change. The observed strain patterns of S waves significantly differ from those of P waves and should contain information about the source mechanism. …