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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.


A Demonstration Of The Infrared Activity Of Carbon Dioxide, Philip Sieg, William Berner, Peter Harnish, Philip C. Nelson 2019 University of Pennsylvania

A Demonstration Of The Infrared Activity Of Carbon Dioxide, Philip Sieg, William Berner, Peter Harnish, Philip C. Nelson

Department of Physics Papers

Before they can talk meaningfully about anthropogenic climate change, students need to grasp basic principles of natural planetary climates, for example, the key role of trace atmospheric gases in setting surface temperature. We describe a dramatic demonstration that scales well for large audiences and that requires as little as ten classroom minutes to show the crucial difference between room air and carbon dioxide gas. Beyond its significance for public policy, the demonstration can serve as a springboard to motivate discussion of important physics concepts such as rotation and vibration spectra.


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 ...


High Resolution Spatial Variability In Spring Snowmelt For An Arctic Shrub-Tundra Watershed, Branden J. Walker, Philip Marsh Dr 2019 Wilfrid Laurier University

High Resolution Spatial Variability In Spring Snowmelt For An Arctic Shrub-Tundra Watershed, Branden J. Walker, Philip Marsh Dr

Theses and Dissertations (Comprehensive)

Arctic tundra environments are characterized by spatially heterogeneous end-of-winter snow cover because of high winds that erode, transport and deposit snow over the winter. This spatially variable end-of-winter snow cover subsequently influences the spatial and temporal variability of snowmelt and results in a patchy snowcover over the melt period. Documenting changes in both snow cover area (SCA) and snow water equivalent (SWE) during the spring melt is essential for understanding hydrological systems, but the lack of high-resolution SCA and SWE datasets that accurately capture micro-scale changes are not commonly available, and do not exist for the Canadian Arctic. This study ...


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 ...


Coupling Between Land–Ocean–Atmosphere And Pronounced Changes In Atmospheric/Meteorological Parameters Associated With The Hudhud Cyclone Of October 2014, Akshansa Chauhan, Rajesh Kumar, Ramesh P. Singh 2018 Sharda University

Coupling Between Land–Ocean–Atmosphere And Pronounced Changes In Atmospheric/Meteorological Parameters Associated With The Hudhud Cyclone Of October 2014, Akshansa Chauhan, Rajesh Kumar, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

India is vulnerable to all kinds of natural hazards associated with land, ocean, biosphere, atmosphere, and snow/glaciers. These natural hazards impact large areas and the population living in the affected regions. India is surrounded by ocean on three sides and is vulnerable to cyclonic activities. Every year cyclones hit the east and west coasts of India, affecting the population living along the coasts and infrastructure and inland areas. The extent of the affected inland areas depends on the intensity of the cyclone. On 12 October 2014, a strong cyclone “Hudhud” hit the east coast of India that caused a ...


Land Use And Land Cover Changes, And Environment And Risk Evaluation Of Dujiangyan City (Sw China) Using Remote Sensing And Gis Techniques, Biswajit Nath, Zheng Niu, Ramesh P. Singh 2018 Chinese Academy of Sciences

Land Use And Land Cover Changes, And Environment And Risk Evaluation Of Dujiangyan City (Sw China) Using Remote Sensing And Gis Techniques, Biswajit Nath, Zheng Niu, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Understanding of the Land Use and Land Cover (LULC) change, its transitions and Landscape risk (LR) evaluation in earthquake-affected areas is important for planning and urban sustainability. In the present study, we have considered Dujiangyan City and its Environs (DCEN), a seismic-prone area close to the 2008 Wenchuan earthquake (8.0 Mw) during 2007–2018. Five different multi-temporal data sets for the years 2007, 2008, 2010, 2015, and 2018 were considered for LULC mapping, followed by the maximum likelihood supervised classification technique. The individual LULC maps were further used in four time periods, i.e., 2007–2018, 2008–2018, 2010 ...


Blue Carbon: Methane Emissions From Managed Saline Ponds In The South Bay Salt Pond Restoration Project, San Francisco Bay, Haley J. Miller, Glenn E. Woerndle, Steve Crooks, Jason K. Keller 2018 Chapman University

Blue Carbon: Methane Emissions From Managed Saline Ponds In The South Bay Salt Pond Restoration Project, San Francisco Bay, Haley J. Miller, Glenn E. Woerndle, Steve Crooks, Jason K. Keller

Biology, Chemistry, and Environmental Sciences Faculty Data Sets

This data set reports net methane (CH4) emissions from managed saline ponds and a restored salt marsh associated with the South Bay Salt Ponds Restoration Project, San Francisco Bay, CA, USA. Associated biogeochemical and physical data are also reported. Data were collected on five sampling dates over the course of the study: November 2016, January 2017, March 2017, June 2017 and August 2017. Logistics (e.g., weather and road conditions) and nesting birds did not allow us to sample all locations during all sampling events.

Methane emissions were measured using static chambers and biogeochemical data were measured on porewater ...


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 ...


Evaluation Of A Sequential Pond System For Detention And Treatment Of Runoff At Skypark, Santa's Village, Elizabeth Caporuscio 2018 California State University, San Bernardino

Evaluation Of A Sequential Pond System For Detention And Treatment Of Runoff At Skypark, Santa's Village, Elizabeth Caporuscio

Electronic Theses, Projects, and Dissertations

Understanding the extent to which human activities impact surface water resources has become increasingly important as both human population growth and related landscape changes impact water quality and quantity across varying geographical scales. Skypark, Santa’s Village is a 233.76-acre tourism-based outdoor recreation area located in Skyforest, California residing within the San Bernardino National Forest. The park is situated at Hooks Creek, the headwaters of the Mojave River Watershed, and is characterized by a diverse landscape that includes forest cover and human development, including impervious surfaces, a restored meadow, and recreational trails. In 2016, Hencks Meadow was considered degraded ...


Timing And Formation Of Linear Dunes South Of The Niobrara River Valley, North-Central Nebraska Sand Hills, Ashley K. Larsen 2018 University of Nebraska-Lincoln

Timing And Formation Of Linear Dunes South Of The Niobrara River Valley, North-Central Nebraska Sand Hills, Ashley K. Larsen

Theses and Dissertations in Geography

The Nebraska Sand Hills is a vast (7500 square kilometer) area of grass-stabilized sand dunes. Larger dunes in the Nebraska Sand Hills formed primarily during the Late Pleistocene, but many underwent widespread reactivation during the Holocene. Recent Optically Stimulated Luminescence (OSL) dating indicates that the last major phase of reactivation in the Sand Hills was during the Medieval Warm Period, approximately 800 years ago. Nevertheless, many questions about the evolution of the dunes remain unanswered, particularly regarding the formation of linear dunes in portions of the Sand Hills.

This study seeks to understand more about the formation of linear dunes ...


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 ...


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 ...


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 ...


Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern 2018 University of Arkansas, Fayetteville

Methanogens, Plausible Extraterrestrial Life Forms On Mars, And Their Tolerance To Increasing Concentrations Of Illite Clay, Chandler Kern

Biological Sciences Undergraduate Honors Theses

Methanogens, some of Earth’s most primitive prokaryotic organisms, are candidates for possible life forms capable of inhabiting Mars. Specifically, four different species (Methanobacterium formicicum, Methanococcus maripaludis, Methanosarcina barkeri, Methanothermobacter wolfeii) were analyzed for their tolerance to the presence of illite clay. Illite is a crystalline mineral that has been identified from regions of Mars’s surface. Results indicated that all four species grew with some success in the illite at different concentrations. This experimentation with methanogens’ abilities to survive and reproduce in the presence of illite allows for a more accurate understanding of the potential capability of microbial growth ...


Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy 2018 University of Nebraska-Lincoln

Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy

Dissertations & Theses in Natural Resources

Grasslands provide food, fiber, and numerous ecosystem services to human populations as well as habitat for wildlife. They are also some of the most endangered ecosystems in the world because of their productive soils and open topography. This problem is exacerbated by the accelerating conversion of grassland to cropland and encroaching trees and shrubs. The quality of remaining grasslands will be of increasing importance because of the biodiversity and vital ecosystem services they provide. Heterogeneity is a term specific to rangeland science that is illustrative of grassland health. Grassland species require very specific and differing habitats and without the variation ...


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 ...


The Role Of Mites In The Construction And Weathering Of Siliceous Biospeleothems, María José López-Galindo 2018 University of Coruña

The Role Of Mites In The Construction And Weathering Of Siliceous Biospeleothems, María José López-Galindo

International Journal of Speleology

Acarines are well-documented as formative elements in the biocenosis of soils. However, their role in the construction and weathering of siliceous speleothems has received very little attention in previous research. The present study describes different groups of cavities (nesting/molting sites) excavated by these organisms in the surface of siliceous speleothems that are deposited in the fissures between various granite boulders in Southern Spain. There is evidence that there are immature stages that would survive the heat and drought of summer in the form of small larvae, or euedaphic nymphs, in the soil. This study provides the first description of ...


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