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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.


Using A Case Study Approach To Teach Invasive Species And Climate Change, Amanda Hoover, Bradley Blaha, Jacob Englin, Madhav P. Nepal, Larry B. Browning, Matt L. Miller, P. Troy White 2019 Lake Preston School District, Lake Preston, South Dakota

Using A Case Study Approach To Teach Invasive Species And Climate Change, Amanda Hoover, Bradley Blaha, Jacob Englin, Madhav P. Nepal, Larry B. Browning, Matt L. Miller, P. Troy White

iLEARN Curriculum Resources

In this teaching module, students will explore emerald ash borer (EAB), its impacts on the ash trees, and how warming temperatures could affect EAB populations. The emerald ash borer is a green buprestid or jewel beetle native to north-eastern Asia that causes devastating disease in ash trees.


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 ...


Geomorphology Of Shell Ridges And Their Effect On The Stabilization Of The Biloxi Marsh, East Louisiana, Frances R. Crawford 2018 University of New Orleans

Geomorphology Of Shell Ridges And Their Effect On The Stabilization Of The Biloxi Marsh, East Louisiana, Frances R. Crawford

University of New Orleans Theses and Dissertations

Extensive shell ridges frame the edges of marsh platforms in parts of the Biloxi Marsh of southeast Louisiana. The exact sources of the shells in these accumulations have not been clearly identified but the most likely source is a combination of shells from modern offshore and shells excavated from buried St. Bernard delta deposits. Larger or fetch-protected ridges remain stable through time, whereas ridges facing open water are more mobile, moving as much as 38 m inland from July 2017 to January 2018. Behind stable ridges, marsh platform biomass is relatively unaffected. When ridges are mobile, vegetation is smothered, leaving ...


Monitoring The Impact Of Groundwater Pumping On Infrastructure Using Geographic Information System (Gis) And Persistent Scatterer Interferometry (Psi), Kirsten DePrekel, El Hachemi Bouali, Thomas Oommen 2018 Michigan Technological University

Monitoring The Impact Of Groundwater Pumping On Infrastructure Using Geographic Information System (Gis) And Persistent Scatterer Interferometry (Psi), Kirsten Deprekel, El Hachemi Bouali, Thomas Oommen

Department of Geological and Mining Engineering and Sciences Publications

Transportation infrastructure is critical for the advancement of society. Bridges are vital for an efficient transportation network. Bridges across the world undergo variable deformation/displacement due to the Earth’s dynamic processes. This displacement is caused by ground motion, which occurs from many natural and anthropogenic events. Events causing deformation include temperature fluctuation, subsidence, landslides, earthquakes, water/sea level variation, subsurface resource extraction, etc. Continual deformation may cause bridge failure, putting civilians at risk, if not managed properly. Monitoring bridge displacement, large and small, provides evidence of the state and health of the bridge. Traditionally, bridge monitoring has been executed ...


Chemical And Morphological Variance In Vitriclastic Shards From Iodp Site U1437: Inferences About Source Regions And Eruptive Mechanisms, Larissa Sleeper 2018 Western Washington University

Chemical And Morphological Variance In Vitriclastic Shards From Iodp Site U1437: Inferences About Source Regions And Eruptive Mechanisms, Larissa Sleeper

Geology Graduate and Undergraduate Student Scholarship

International Ocean Discovery Program (IODP) Expedition 350 recovered roughly 2000 meters of volcaniclastic material. This paper focuses on the first 100 meters of this core which was almost entirely composed of tuffaceous mud. Tiny (micron) vitriclastic shards within this mud were analyzed to determine their chemistry and their morphology to make inferences about their source environment and eruptive mechanisms.


Holocene Formation And Evolution Of Horn Island, Mississippi, Usa, Nina Gal 2018 The University of Southern Mississippi

Holocene Formation And Evolution Of Horn Island, Mississippi, Usa, Nina Gal

Master's Theses

Horn Island, one of the most stable barriers along the Mississippi-Alabama chain, provides critical habitat, helps regulate estuarine conditions in the Mississippi Sound, and reduces wave energy and storm surge for the mainland. This study integrates 2,200 km of high-resolution geophysics, 35 sediment cores, and 15 radiocarbon ages to better understand the formation and evolution of the island in response to sea-level rise, storms, and antecedent geology. The Biloxi and Pascagoula incised valleys converge at Horn Island and have played a profound role in the evolution of the system. Within the incised valleys, numerous shallow paleochannels between 4 and ...


Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis 2018 The University of Southern Mississippi

Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis

Master's Theses

Coastal systems in the Gulf of Mexico are threatened to reduced sediment supply, storm impacts and relative sea level rise (RSLR). The geologic record can provide insights of geomorphic threshold crossings (formation, progradation, transgression, destruction) to these forcing mechanisms to predict future barrier evolution to climate change. The stratigraphic framework and antecedent topography directly influence coastal evolution over geologic timescales. This study synthesizes ~2100km of geophysical data, 700+ sediment cores, and 63 radiocarbon dates to regionally map two sequence boundaries, multiple ravinement surfaces and fourteen depositional facies. One marine isotope stage (MIS) 6 valley’s fill provided up to 300 ...


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 ...


Subsurface Analysis Of Mississippian Tripolitic Chert In Northwest Arkansas, Thomas Jason Liner 2018 University of Arkansas, Fayetteville

Subsurface Analysis Of Mississippian Tripolitic Chert In Northwest Arkansas, Thomas Jason Liner

Theses and Dissertations

Over the past 70 years the Mississippian strata of Northwest Arkansas have been studied in great detail. The study area is located on the escarpment between the Boston Mountains Plateau and the Springfield Plateau where a surface occurrence of Mississippian age rock allows for access to outcrops in close proximity to gas wells that encounter subsurface Mississippian strata. Many outcrops found in Northwest Arkansas expose Lower Mississippian (Kinderhookian-Osagean) strata that represent a full third order transgressive/regressive sequence that is unconformity bounded. These Mississippian outcrops are commonly treated as surface analogs to the Mississippi Lime Play in North Central Oklahoma ...


An Integrated Well Log And 3d Seismic Interpretation Of Missourian Clinoforms, Osage County, Oklahoma, Abram Max Barker 2018 University of Arkansas, Fayetteville

An Integrated Well Log And 3d Seismic Interpretation Of Missourian Clinoforms, Osage County, Oklahoma, Abram Max Barker

Theses and Dissertations

Integrated analysis of well and geophysical data can provide detailed geologic interpretation of the subsurface in Osage County, Oklahoma. Systems tracts and depositional system successions can be interpreted at marginal seismic resolution using well log motif with seismic reflector character within a depositional context. Shelf-prism and subaqueous, delta-scale clinoforms of Missourian age observed in 3D seismic were interpreted with greater sequence stratigraphic detail when coupled with wireline well logs. The Late Pennsylvanian Midcontinent Sea was thought to be approximately 150 feet average depth across the southern Midcontinent during the Missourian Stage, and deepen towards the Arkoma and Anadarko Basins to ...


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 ...


Assessing Ground Penetrating Radar's Ability To Image Subsurface Characteristics Of Icy Debris Fans In Alaska And New Zealand, Robert W. Jacob, Jeffrey M. Trop, R. Craig Kochel 2018 Bucknell University

Assessing Ground Penetrating Radar's Ability To Image Subsurface Characteristics Of Icy Debris Fans In Alaska And New Zealand, Robert W. Jacob, Jeffrey M. Trop, R. Craig Kochel

Faculty Journal Articles

Icy debris fans have recently been described as fan shaped depositional landforms associated with (or formed during) deglaciation, however, the subsurface characteristics remain essentially undocumented. We used ground penetrating radar (GPR) to non-invasively investigate the subsurface characteristics of icy debris fans (IDFs) at McCarthy Glacier, Alaska, USA and at La Perouse Glacier, South Island of New Zealand. IDFs are largely unexplored paraglacial landforms in deglaciating alpine regions at the mouths of bedrock catchments between valley glaciers and icecaps. IDFs receive deposits of mainly ice and minor lithic material through different mass-flow processes, chiefly ice avalanche and to a lesser extent ...


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 ...


Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński 2018 University of Warsaw

Compositional And Thermodynamic Variability In A Stratified Magma Chamber: Evidence From The Green Tuff Ignimbrite (Pantelleria, Italy)., Katarzyna M. Liszewska, John C. White, Ray Macdonald, Bogusław Bagiński

EKU Faculty and Staff Scholarship

The Green Tuff Ignimbrite, Pantelleria, is compositionally zoned from pantellerite at the base to comenditic trachyte at the top, the variation apparently representing an inverted vertical zonation in the pre-eruptive reservoir. The main phenocryst assemblages are alkali feldspar + olivine + clinopyroxene + ilmenite + apatite in the trachytes and alkali feldspar + aenigmatite + clinopyroxene + quartz in the rhyolites. Thermodynamic modelling indicates that the temperature range was ~900–700°C, fO2 FMQ –1.5 to FMQ –0.5 (where FMQ is fayalite–magnetite–quartz buffer) and aSiO2 (relative to quartz saturation) 0.74–1.00. Melt water contents ranged from ~1wt % in the trachytes to ...


Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas, William Stephen Denham 2018 University of Arkansas, Fayetteville

Subsurface Stratigraphic Interpretation Of The Lower Atoka Formation, Northern Arkoma Basin, Arkansas, William Stephen Denham

Theses and Dissertations

The Arkoma Basin is a Carboniferous peripheral foreland basin creating a structural depression covering an approximate area of 33,800 miles2 that extends through east-central Oklahoma and west-central Arkansas. The entire basin fill includes Pre-Mississippian carbonate shelf deposits, Mississippian marine carbonates and black shales, and Pennsylvanian mixed carbonated/clastic and shore zone/deltaic deposits. The Lower Atoka formation (Pennsylvanian) occurs in outcrop along the southern Boston Mountain Plateau in northern Arkansas and extends into the subsurface of the Arkoma Basin over an area of 2,300 miles2. The Lower Atoka ranges from 600 to 1500 feet in thickness and represents ...


Margaret White Springs Recharge Study, Buffalo National River, North-Central Arkansas, Usa, Ashlon Elizabeth Leonard 2018 University of Arkansas, Fayetteville

Margaret White Springs Recharge Study, Buffalo National River, North-Central Arkansas, Usa, Ashlon Elizabeth Leonard

Theses and Dissertations

Margaret White Springs (MWS) is one of the largest springs in the middle section of the Buffalo National River (BNR) and contributes several tens of cubic feet per second of flow to river discharge on average, yet the source of the water has not been fully studied or documented. The spring is located approximately 4 miles downstream from Robertson Hole, a losing reach of the river. At Robertson Hole the river loses a significant amount of flow to groundwater, which during the dry season (summer) can be as much as 100%. Flow in the main channel is re-established at MWS ...


Molecular Fossils From Phytoplankton Reveal Secular Pco2 Trend Over The Phanerozoic, Caitlyn R. Witkowski, Johan W. H. Weijers, Brian S. Blais, Stefan Schouten, Jaap S. Sinninghe Damsté 2018 Utrecht University

Molecular Fossils From Phytoplankton Reveal Secular Pco2 Trend Over The Phanerozoic, Caitlyn R. Witkowski, Johan W. H. Weijers, Brian S. Blais, Stefan Schouten, Jaap S. Sinninghe Damsté

Science and Technology Faculty Journal Articles

Past changes in the atmospheric concentration of carbon dioxide (PCO2) have had a major impact on earth system dynamics; yet, reconstructing secular trends of past PCO2 remains a prevalent challenge in paleoclimate studies. The current long-term PCO2reconstructions rely largely on the compilation of many different proxies, often with discrepancies among proxies, particularly for periods older than 100 million years (Ma). Here, we reconstructed Phanerozoic PCO2 from a single proxy: the stable carbon isotopic fractionation associated with photosynthesis (Ɛp) that increases as PCO2 increases. This concept has been widely applied to alkenones, but here, we expand ...


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 ...


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