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Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed 2019 University of Tennessee

Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed

University of Tennessee Honors Thesis Projects

No abstract provided.


Comparing Dietary Differences Among The Hornless Artiodactyl Ruminants Hypertragulus, Hypisodus, And Leptomeryx From The Early Oligocene (Orellan) Brule Formation, Toadstool Geologic Park, Nebraska, Holly Chien Seyler 2019 University of Colorado at Boulder

Comparing Dietary Differences Among The Hornless Artiodactyl Ruminants Hypertragulus, Hypisodus, And Leptomeryx From The Early Oligocene (Orellan) Brule Formation, Toadstool Geologic Park, Nebraska, Holly Chien Seyler

Museum and Field Studies Graduate Theses & Dissertations

The Early Oligocene (Orellan) in the North American Western Interior is marked by a cooler and dryer climate than the late Eocene (Chadronian). New mammalian taxa appeared while other groups already present began to diversify. This study takes a closer look at the diversification of hornless ruminant artiodactyls present in the Latest Orellan Merycoidodon bullatus Interval Zone through an analysis of 70 specimens from three closely related species: Hypertragulus (27), Hypisodus (18), and Leptomeryx (25) from a single locality in Toadstool Geologic Park, Nebraska. Specifically, we took a closer look at the hypsodonty index, mesowear, and tooth volume, which have ...


Designing A Protected Area To Safeguard Imperiled Species From Urbanization, Stephanie S. Romanach, Brad Stith, Fred A. Johnson 2018 U.S. Geological Survey, Wetland and Aquatic Research Center

Designing A Protected Area To Safeguard Imperiled Species From Urbanization, Stephanie S. Romanach, Brad Stith, Fred A. Johnson

USGS Staff -- Published Research

Reserve design is a process that can address ecological, social, and political factors to identify parcels of land needed to sustain wildlife populations and other natural resources. Acquisition of parcels for a large terrestrial reserve is difficult because it typically occurs over a long timeframe and thus invokes consideration of future conditions such as climate and urbanization changes. In central Florida, the U.S. government has authorized a new protected area, the Everglades Headwaters National Wildlife Refuge. The new refuge will host important threatened and endangered species and habitats, and will be located to allow for species adaptation from climate ...


New Ca-Id-Tims Detrital Zircon Constraints On Middle Neoproterozoic Sedimentary Successions, Southwestern United States, Abigail R. Bullard 2018 Utah State University

New Ca-Id-Tims Detrital Zircon Constraints On Middle Neoproterozoic Sedimentary Successions, Southwestern United States, Abigail R. Bullard

All Graduate Theses and Dissertations

Three related sedimentary successions located in Arizona, Utah, and California were deposited in basins on proto-North America during the early rifting of Rodinia (~780 Mya). Previous detrital zircon U-Pb maximum ages for the units are inexact, making it difficult to piece together what happened at this point in Earth history.

We report better maximum age constraints on these units obtained by subjecting detrital zircons to high-precision CA-ID-TIMS analysis, which provide more exact 206 Pb/238U ages. These new data significantly improve the precision for the base of the ChUMP units, with an average age of 775. 63 ± 0.27 Ma ...


The Influence Of Mechanical Stratigraphy On Thrust-Ramp Nucleation And Propagation Of Thrust Faults, Sarah S. Wigginton 2018 Utah State University

The Influence Of Mechanical Stratigraphy On Thrust-Ramp Nucleation And Propagation Of Thrust Faults, Sarah S. Wigginton

All Graduate Theses and Dissertations

Our current understanding of thrust fault kinematics predicts that thrust faults nucleate on low angle, weak surfaces before they propagate upward and forms a higher angle ramp. While this classic kinematic and geometric model serves well in some settings, it does not fully consider the observations of footwall deformation beneath some thrust faults. We examine an alternative end-member model of thrust fault formation called “ramp-first” fault formation. This model hypothesizes that in mechanically layered rocks, thrust ramps nucleate in the structurally strong units, and that faults can propagate both upward and downward into weaker units forming folds at both fault ...


Interpreting The Origin And Evolution Of ‘Karst’ Features From A Siliceous Hydrothermal Terrane: A Case Study From The Upper Geyser Basin In Yellowstone National Park, Usa, Kevin W. Blackwood, Lainee A. Sanders, Stacy I. Gantt-Blackwood 2018 East Central University

Interpreting The Origin And Evolution Of ‘Karst’ Features From A Siliceous Hydrothermal Terrane: A Case Study From The Upper Geyser Basin In Yellowstone National Park, Usa, Kevin W. Blackwood, Lainee A. Sanders, Stacy I. Gantt-Blackwood

International Journal of Speleology

The Upper Geyser Basin in Yellowstone National Park occurs over a siliceous hydrothermal terrane containing numerous hot springs and geysers. The pool and vent-conduit geometries of these hydrothermal features share a resemblance to conventional karst features known from other rock types, suggesting karst processes could be responsible for their origin and/or evolution. Hypogene speleogenesis is a cave-forming process in which the formation of caves is decoupled from and occurs independently of surface recharge. The geologic setting for hypogene speleogenesis typically occurs at the distal end of regional groundwater systems wherein the hydrogeology is manifested by ascending fluids and/or ...


Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu 2018 Missouri University of Science and Technology

Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu

Kelly H. Liu

The 410 and 660 km discontinuities (d410 and d660, respectively) beneath Alaska and adjacent areas are imaged by stacking 75,296 radial receiver functions recorded by 438 broadband seismic stations with up to 30 years of recording period. When the 1-D IASP91 Earth model is used for moveout correction and time depth conversion, significant and spatially systematic variations in the apparent depths of the d410 and d660 are observed. The mean apparent depth of the d410 and d660 for the entire study area is 417 ± 12 km and 665 ± 12 km, respectively, and the mean mantle transition zone (MTZ) thickness ...


Characteristics Of The Mantle Flow System Beneath The Indochina Peninsula Revealed By Teleseismic Shear Wave Splitting Analysis, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanh Phon Le, Jinyao Gao 2018 Missouri University of Science and Technology

Characteristics Of The Mantle Flow System Beneath The Indochina Peninsula Revealed By Teleseismic Shear Wave Splitting Analysis, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanh Phon Le, Jinyao Gao

Kelly H. Liu

Numerous geoscientific investigations have been conducted on the southeastern Tibetan Plateau and adjacent areas for understanding crustal and mantle deformation associated with the indentation of the Indian Plate into Eurasia. A number of key issues, such as the causes of a sudden change of fast polarization orientations from N-S to almost E-W at approximately 26°N revealed by shear wave splitting (SWS) studies, and the geodynamic implications of the transition still remain enigmatic, partially due to the lack of sufficient SWS measurements on the Indochina Peninsula. Here we employ the SWS technique to systematically illuminate upper mantle anisotropy beneath the ...


Receiver Function Imaging Of Mantle Transition Zone Discontinuities Beneath The Tanzania Craton And Adjacent Segments Of The East African Rift System, Muchen Sun, Kelly H. Liu, Xiaofei Fu, Stephen S. Gao 2018 Missouri University of Science and Technology

Receiver Function Imaging Of Mantle Transition Zone Discontinuities Beneath The Tanzania Craton And Adjacent Segments Of The East African Rift System, Muchen Sun, Kelly H. Liu, Xiaofei Fu, Stephen S. Gao

Kelly H. Liu

The mantle transition zone (MTZ) discontinuities beneath the Tanzania Craton and the Eastern and Western Branches of the East African Rift System are imaged by stacking over 7,100 receiver functions. The mean thickness of the MTZ beneath the Western Branch and Tanzania Craton is about 252 km, which is comparable to the global average and is inconsistent with the existence of present-day thermal upwelling originating from the lower mantle. In contrast, beneath the Eastern Branch, an up to 30 km thinning of the MTZ is observed and is attributable to upwelling of higher temperature materials from either the upper ...


Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu 2018 Missouri University of Science and Technology

Topography Of The Mantle Transition Zone Discontinuities Beneath Alaska And Its Geodynamic Implications: Constraints From Receiver Function Stacking, Haider H. Dahm, Stephen S. Gao, Fansheng Kong, Kelly H. Liu

Stephen S. Gao

The 410 and 660 km discontinuities (d410 and d660, respectively) beneath Alaska and adjacent areas are imaged by stacking 75,296 radial receiver functions recorded by 438 broadband seismic stations with up to 30 years of recording period. When the 1-D IASP91 Earth model is used for moveout correction and time depth conversion, significant and spatially systematic variations in the apparent depths of the d410 and d660 are observed. The mean apparent depth of the d410 and d660 for the entire study area is 417 ± 12 km and 665 ± 12 km, respectively, and the mean mantle transition zone (MTZ) thickness ...


Receiver Function Imaging Of Mantle Transition Zone Discontinuities Beneath The Tanzania Craton And Adjacent Segments Of The East African Rift System, Muchen Sun, Kelly H. Liu, Xiaofei Fu, Stephen S. Gao 2018 Missouri University of Science and Technology

Receiver Function Imaging Of Mantle Transition Zone Discontinuities Beneath The Tanzania Craton And Adjacent Segments Of The East African Rift System, Muchen Sun, Kelly H. Liu, Xiaofei Fu, Stephen S. Gao

Stephen S. Gao

The mantle transition zone (MTZ) discontinuities beneath the Tanzania Craton and the Eastern and Western Branches of the East African Rift System are imaged by stacking over 7,100 receiver functions. The mean thickness of the MTZ beneath the Western Branch and Tanzania Craton is about 252 km, which is comparable to the global average and is inconsistent with the existence of present-day thermal upwelling originating from the lower mantle. In contrast, beneath the Eastern Branch, an up to 30 km thinning of the MTZ is observed and is attributable to upwelling of higher temperature materials from either the upper ...


Characteristics Of The Mantle Flow System Beneath The Indochina Peninsula Revealed By Teleseismic Shear Wave Splitting Analysis, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanh Phon Le, Jinyao Gao 2018 Missouri University of Science and Technology

Characteristics Of The Mantle Flow System Beneath The Indochina Peninsula Revealed By Teleseismic Shear Wave Splitting Analysis, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanh Phon Le, Jinyao Gao

Stephen S. Gao

Numerous geoscientific investigations have been conducted on the southeastern Tibetan Plateau and adjacent areas for understanding crustal and mantle deformation associated with the indentation of the Indian Plate into Eurasia. A number of key issues, such as the causes of a sudden change of fast polarization orientations from N-S to almost E-W at approximately 26°N revealed by shear wave splitting (SWS) studies, and the geodynamic implications of the transition still remain enigmatic, partially due to the lack of sufficient SWS measurements on the Indochina Peninsula. Here we employ the SWS technique to systematically illuminate upper mantle anisotropy beneath the ...


Improving The Total Organic Carbon Estimation Of The Eagle Ford Shale With Density Logs By Considering The Effect Of Pyrite, Shuxian Jiang, Mehdi Mokhtari, David M. Borrok, Jim Lee 2018 Missouri University of Science and Technology

Improving The Total Organic Carbon Estimation Of The Eagle Ford Shale With Density Logs By Considering The Effect Of Pyrite, Shuxian Jiang, Mehdi Mokhtari, David M. Borrok, Jim Lee

David M. Borrok

Pyrite is a common mineral with a higher density than most other minerals in the Eagle Ford Shale formation. Hence, if pyrite is not considered in the total organic carbon (TOC) estimation, based on density logs, it may lead to errors. In order to improve the accuracy of the TOC estimation, we propose an updated TOC estimation method that incorporates the concentration of pyrite and organic porosity. More than 15 m of Eagle Ford Shale samples were analyzed using Rock-Eval pyrolysis, X-ray fluorescence (XRF), and X-ray diffraction (XRD). TOC, elemental concentration, and mineralogical data were analyzed for a better understanding ...


Natural Trace Element Salinization Of The Jemez River, New Mexico By Geothermal Springs And Major Tributaries, Jon K. Golla, Laura J. Crossey, Abdul-Mehdi S. Ali, Karl E. Karlstrom 2018 University of New Mexico - Main Campus

Natural Trace Element Salinization Of The Jemez River, New Mexico By Geothermal Springs And Major Tributaries, Jon K. Golla, Laura J. Crossey, Abdul-Mehdi S. Ali, Karl E. Karlstrom

Shared Knowledge Conference

The Jemez River (JR), a tributary of the Rio Grande, is in north-central New Mexico within the Jemez Mountains, which houses the active, high-temperature (≤ 300 oC), liquid-dominated Valles Caldera geothermal system (VC). This work focuses on the northern portion of the JR, spanning a reach from the East Fork JR to the town of San Ysidro. Previous decadal work during low-flow or baseflow conditions (~10-20 cfs) has identified and characterized significant major-solute contributions from two outflow expressions of the VC, Soda Dam Springs and Jemez Hot Springs, and two major tributaries, Rio San Antonio and Rio Guadalupe. There is generally ...


15 - Identifying Ancient River Channels And Faces Using Ground Penetrating Radar: Brunswick, Georgia, Usa, Ken Taylor 2018 University of North Georgia

15 - Identifying Ancient River Channels And Faces Using Ground Penetrating Radar: Brunswick, Georgia, Usa, Ken Taylor

Georgia Undergraduate Research Conference (GURC)

The Princess Anne formation has been previously interpreted as a late-Pleistocene barrier island chain that was deposited ~40 thousand years ago, extending across Brunswick, GA. Historically, this geologic formation has yielded exceptionally well-preserved fossils such as Mammuthus columbi (Columbian mammoth) and Bison latifrons (long-horned bison). Previous studies have hypothesized that these fossils were situated in “cut-and-fill” channel structures (i.e., paleochannels) that later dissected the barrier island deposit ~20 thousand years ago. We performed a high-resolution (200 MHz) ground-penetrating radar (GPR) survey to identify any channel-like structures, in addition to subsurface features related to the formation and evolution of the ...


Groundwater Contamination At Coal Ash Deposit Sites In Kentucky, Brandon Rose 2018 Murray State University

Groundwater Contamination At Coal Ash Deposit Sites In Kentucky, Brandon Rose

Scholars Week

No abstract provided.


Kentucky Flood And Flash Flood Comparison Of 1996 And 2017 Using Gis, Harrison Kelly 2018 Murray State University

Kentucky Flood And Flash Flood Comparison Of 1996 And 2017 Using Gis, Harrison Kelly

Scholars Week

No abstract provided.


Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch 2018 Missouri University of Science and Technology

Clustering Data Of Mixed Categorical And Numerical Type With Unsupervised Feature Learning, Dao Lam, Mingzhen Wei, Donald C. Wunsch

Donald C. Wunsch

Mixed-type categorical and numerical data are a challenge in many applications. This general area of mixed-type data is among the frontier areas, where computational intelligence approaches are often brittle compared with the capabilities of living creatures. In this paper, unsupervised feature learning (UFL) is applied to the mixed-type data to achieve a sparse representation, which makes it easier for clustering algorithms to separate the data. Unlike other UFL methods that work with homogeneous data, such as image and video data, the presented UFL works with the mixed-type data using fuzzy adaptive resonance theory (ART). UFL with fuzzy ART (UFLA) obtains ...


Explosive Dust Test Vessel Comparison Using Pulverized Pittsburgh Coal, Jacob Miller, Jay Schafler, Phillip R. Mulligan, Robert Eades, Kyle A. Perry, Catherine E. Johnson 2018 Missouri University of Science and Technology

Explosive Dust Test Vessel Comparison Using Pulverized Pittsburgh Coal, Jacob Miller, Jay Schafler, Phillip R. Mulligan, Robert Eades, Kyle A. Perry, Catherine E. Johnson

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Explosions of coal dust are a major safety concern within the coal mining industry. The explosion and subsequent fires caused by coal dust can result in significant property damage, loss of life in underground coal mines and damage to coal processing facilities. The United States Bureau of Mines conducted research on coal dust explosions until 1996 when it was dissolved. In the following years, the American Society for Testing and Materials (ASTM) developed a test standard, ASTM E1226, to provide a standard test method characterizing the “explosibility” of particulate solids of combustible materials suspended in air. The research presented herein ...


Further Evidence For The Invasion And Establishment Of Pterois Volitans (Teleostei: Scorpaenidae) Along The Atlantic Coast Of The United States, H. Scott Meister, David M. Wyanski, Joshua K. Loefer, Steve W. Ross, Andrea M. Quattrini, Kenneth J. Sulak 2018 South Carolina Department of Natural Resources, Marine Resources Research Institute,

Further Evidence For The Invasion And Establishment Of Pterois Volitans (Teleostei: Scorpaenidae) Along The Atlantic Coast Of The United States, H. Scott Meister, David M. Wyanski, Joshua K. Loefer, Steve W. Ross, Andrea M. Quattrini, Kenneth J. Sulak

USGS Staff -- Published Research

We document the continues population expansion of red lionfish, Pterois volitans, the first documented successful introduction of an invasive marine fish species from the western Pacific to Atlantic coastal water of the United States. Red lionfish are indigenous to the Indo-Pacific and have apparently established one or more breeding population on reefs off the southeastern United States. Fifty-nine specimens, most presumably adult red lionfish, were documented or collected on live-bottom reefs North Carolina, South Caroline, and Florida, and on a manmade structure off Georgia. Observation/collection depths and bottom water temperatures for these fish ranged from 4-99 m and 13 ...


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