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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 ...


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 ...


Perennial Biomass Crop Establishment, Community Characteristics, And Productivity In The Upper Us Midwest: Effects Of Cropping Systems Seed Mixtures And Biochar Applications, Catherine L. Bonin, Rivka B. Fidel, Chumki Banik, David A. Laird, Robert Mitchell, Emily A. Heaton 2018 Iowa State University

Perennial Biomass Crop Establishment, Community Characteristics, And Productivity In The Upper Us Midwest: Effects Of Cropping Systems Seed Mixtures And Biochar Applications, Catherine L. Bonin, Rivka B. Fidel, Chumki Banik, David A. Laird, Robert Mitchell, Emily A. Heaton

Agronomy Publications

Native perennial plants have potential as bioenergy feedstocks, but their use is currently limited by relatively long establishment times and low biomass yields. Some research suggests that incorporating plant species diversity and applying biochar as a soil amendment might alleviate these limitations by creating a more resilient crop and soil system. The objective of this research was to investigate how 1) seeded plant diversity and 2) biochar soil amendments interact to affect the establishment, yield, and plant species composition of biomass cropping systems during the first four years of growth on productive soils. We measured species emergence, cover, peak and ...


A Sub-Millennial Sediment Record Of Ice-Stream Retreat And Meltwater Storage In The Baltic Ice Lake During The Bølling-Allerød Interstadial, April Lynn Kelly, Sandra Passchier 2018 Montclair State University

A Sub-Millennial Sediment Record Of Ice-Stream Retreat And Meltwater Storage In The Baltic Ice Lake During The Bølling-Allerød Interstadial, April Lynn Kelly, Sandra Passchier

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The rapid retreat of the Baltic Ice Stream and the development of the Baltic Ice Lake is assessed using data from sediment cores retrieved from three sub-basins in the southern Baltic Sea. Hydraulic piston coring by the International Ocean Discovery Program (IODP) recovered for the first time intact glacial lake sequences overlying diamictons and other ice-contact deposits at Sites M0063, M0064 and M0065. Based on the particle size and bulk sediment chemical composition the glacial lake sediments were subdivided into a proximal and a distal varve sequence. The origin of a dark, lithologically distinct horizon between the proximal and distal ...


Theory On Thermodynamic Constraints To Biogeochemical And Metabolic Diversity, Jordan Okie, Everett Shock 2018 Arizona State University

Theory On Thermodynamic Constraints To Biogeochemical And Metabolic Diversity, Jordan Okie, Everett Shock

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. McFarlane 2018 Carleton University

On Biospeleothems From A Venezuelan Tepui Cave: U-Th Dating, Growth Rates, And Morphology, Joyce Lundberg, Charles Brewer-Carías, Donald A. Mcfarlane

International Journal of Speleology

Seven silica biospeleothems from Cueva Charles Brewer, Chimantá Plateau, Venezuela have been successfully U-Th dated despite very low U and high detrital Th concentrations. Growth rates are low, between ~100 to ~800 µm/ka, and are greater closer to water level. Dates in unaltered material are in good stratigraphic order, but secondary silicification may compromise the U-Th system, yielding unreliable sequences of ages. Detritally-enriched layers correlate with global climate cycles of the Late Quaternary, in particular the cooler, drier phases of MIS 5d, 5a, and 4. SEM studies indicate that the peloidal material is made up of silica nano-particles assembled ...


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 ...


Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel 2018 Iowa State University

Spatial Structuring Of Cellulase Gene Abundance And Activity In Soil, Jinlyung Choi, Elizabeth Bach, Jaejin Lee, Jared Flater, Shane Dooley, Adina Howe, Kirsten S. Hofmockel

Agricultural and Biosystems Engineering Publications

Microbial mechanisms controlling cellulose degradation in soil habitats remains a critical knowledge gap in understanding and modeling terrestrial carbon-cycling. We investigated land management and soil micro-habitat influences on soil bacterial communities and distribution of cellulose-degrading enzyme genes in three bioenergy cropping systems (corn, prairie, and fertilized prairie). Within the soil, aggregates have been examined as potential micro- habitats with specific characteristics influencing resource partitioning and regulation, thus we also investigated genes associated with cellulose degradation within soil aggregate fractions from the fertilized prairie system. Soil bacterial communities and carbon-cycling gene presence varied across land management and soil microhabitats. Examination of ...


Legacy Effects Of Long-Term Nitrogen Fertilizer Application On The Fate Of Nitrogen Fertilizer Inputs In Continuous Maize, Hanna J. Poffenbarger, John E. Sawyer, Daniel W. Barker, Daniel C. Olk, Johan Six, Michael J. Castellano 2018 Iowa State University

Legacy Effects Of Long-Term Nitrogen Fertilizer Application On The Fate Of Nitrogen Fertilizer Inputs In Continuous Maize, Hanna J. Poffenbarger, John E. Sawyer, Daniel W. Barker, Daniel C. Olk, Johan Six, Michael J. Castellano

Agronomy Publications

Nitrogen fertilizer management can impact soil organic C (SOC) stocks in cereal-based cropping systems by regulating crop residue inputs and decomposition rates. However, the impact of long-term N fertilizer management, and associated changes in SOC quantity and quality, on the fate of N fertilizer inputs is uncertain. Using two 15-year N fertilizer rate experiments on continuous maize (Zea mays L.) in Iowa, which have generated gradients of SOC, we evaluated the legacy effects of N fertilizer inputs on the fate of added N. Across the historical N fertilizer rates, which ranged from 0 to 269 kg N ha−1 yr ...


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 ...


Structural Evolution And Petroleum Potential Of A Cambrian Intracratonic Rift System: Mississippi Valley Graben, Rough Creek Graben, And Rome Trough, John B. Hickman, David C. Harris 2018 University of Kentucky

Structural Evolution And Petroleum Potential Of A Cambrian Intracratonic Rift System: Mississippi Valley Graben, Rough Creek Graben, And Rome Trough, John B. Hickman, David C. Harris

Kentucky Geological Survey Report of Investigations

Drilling and geophysical data demonstrate that the Mississippi Valley Graben, Rough Creek Graben, and Rome Trough are fault-bounded structures filled with as much as 27,000 ft of Cambrian sediments. Data including stratigraphic tops from 1,764 wells, 106 seismic profiles, aeromagnetic and gravity surveys, and mapped surface geology at a scale of 1:24,000 were used to study seven stratigraphic packages across parts of Kentucky, Ohio, Indiana, Illinois, Missouri, and Tennessee. Detailed analysis of the thickness patterns of these stratigraphic packages was used to interpret the locations and timing of movement along major fault systems in the study ...


Marine Threats Overlap Key Foraging Habitat For Two Imperiled Sea Turtle Species In The Gulf Of Mexico, Kristen M. Hart, Autumn R. Iverson, Ikuko Fujisaki, Margaret M. Lamont, David Bucklin, Donna J. Shaver 2018 Wetland and Aquatic Research Center, U.S. Geological Survey

Marine Threats Overlap Key Foraging Habitat For Two Imperiled Sea Turtle Species In The Gulf Of Mexico, Kristen M. Hart, Autumn R. Iverson, Ikuko Fujisaki, Margaret M. Lamont, David Bucklin, Donna J. Shaver

USGS Staff -- Published Research

Effective management of human activities affecting listed species requires understanding both threats and animal habitat-use patterns. However, the extent of spatial overlap between high-use foraging areas (where multiple marine species congregate) and anthropogenic threats is not well-known. Our modeling approach incorporates data on sea turtle spatial ecology and a suite of threats in the Gulf of Mexico to identify and map “hot spots” of threats to two imperiled turtle species. Of all 820 “high” threats grid cells, our tracked turtles foraged at least 1 day in 77% of them. Although threat data were not available outside the U.S. Exclusive ...


Conservation Agriculture Practices Increase Potentially Mineralizable Nitrogen: A Meta-Analysis, Navreet K. Mahal, Michael J. Castellano, Fernando E. Miguez 2018 Iowa State University

Conservation Agriculture Practices Increase Potentially Mineralizable Nitrogen: A Meta-Analysis, Navreet K. Mahal, Michael J. Castellano, Fernando E. Miguez

Agronomy Publications

Potentially mineralizable nitrogen (PMN) is considered an important indicator of soil health. Cropping systems management can affect PMN. However, the effect size and relationship with crop yield across specific management practices remain uncertain. We conducted a quantitative review to understand how conservation agriculture management practices affect PMN including N fertilizer application, cropping system diversity, and tillage system as well as the relationship of crop yield with PMN. Data were extracted from 43 studies published in peer-reviewed journals, providing 494 paired comparisons of PMN and 26 paired comparisons of PMN and yield across selected crop management practices. In our meta-analysis, the ...


The Sisal Database: A Global Resource To Document Oxygen And Carbon Isotope Records From Speleothems, Kamolphat Atsawawaranunt, Laia Comas-Bru, Sahar Amirnezhad Mozhdehi, Michael Deininger, Sandy P. Harrison, Andy Baker, Meighan Boyd, Nikita Kaushal, Syed Masood Ahmad, Yassine Ait Brahim, Monica Arienzo, Petra Bajo, Kerstin Braun, Yuval Burstyn, Sakonvan Chawchai, Wuhui Duan, István Gábor Hatvani, Jun Hu, Zoltán Kern, Inga Labuhn, Matthew Lachniet, Franziska A. Lechleitner, Andrew Lorrey, Carlos Pérez-Mejías, Robyn Pickering, Nick Scroxton, SISAL Working Group Members 2018 Reading University

The Sisal Database: A Global Resource To Document Oxygen And Carbon Isotope Records From Speleothems, Kamolphat Atsawawaranunt, Laia Comas-Bru, Sahar Amirnezhad Mozhdehi, Michael Deininger, Sandy P. Harrison, Andy Baker, Meighan Boyd, Nikita Kaushal, Syed Masood Ahmad, Yassine Ait Brahim, Monica Arienzo, Petra Bajo, Kerstin Braun, Yuval Burstyn, Sakonvan Chawchai, Wuhui Duan, István Gábor Hatvani, Jun Hu, Zoltán Kern, Inga Labuhn, Matthew Lachniet, Franziska A. Lechleitner, Andrew Lorrey, Carlos Pérez-Mejías, Robyn Pickering, Nick Scroxton, Sisal Working Group Members

Geoscience Faculty Publications

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide out-of-sample evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (δ18O, δ13C) measurements are ...


Evidence For Subsurface Origin Of Boulder Caves, Roofed Slots And Boulder-Filled Canyons (Broumov Highland, Czechia), Filip Duszyński, Kacper Jancewicz, Piotr Migoń 2018 University of Wrocław

Evidence For Subsurface Origin Of Boulder Caves, Roofed Slots And Boulder-Filled Canyons (Broumov Highland, Czechia), Filip Duszyński, Kacper Jancewicz, Piotr Migoń

International Journal of Speleology

The backslope of a sandstone cuesta in the Broumov Highland (Czechia) is cut by a complex network of canyons. Long sections of canyons have thick boulder fills which are difficult to reconcile with simple rock fall and talus development scenario. Boulder caves occur within these fills and their lowermost parts are drained by streams that evacuate fine loose sandy material produced by weathering and mechanical erosion. These boulder fills are explained as largely in situ, residual features, left after subsurface selective disintegration of rock mass, mainly joint-guided, and removal of grains by underground water. Evacuation of fines leaves voids into ...


Little Lasting Impact Of The Paleocene-Eocene Thermal Maximum On Shallow Marine Molluscan Faunas, Linda Ivany, Carlie Pietsch, John Handley, Rowan Lockwood, Warren Allmon, Jocelyn Sessa 2018 Syracuse University

Little Lasting Impact Of The Paleocene-Eocene Thermal Maximum On Shallow Marine Molluscan Faunas, Linda Ivany, Carlie Pietsch, John Handley, Rowan Lockwood, Warren Allmon, Jocelyn Sessa

Faculty Publications

Global warming, acidification, and oxygen stress at the Paleocene-Eocene Thermal Maximum (PETM) are associated with severe extinction in the deep sea and major biogeographic and ecologic changes in planktonic and terrestrial ecosystems, yet impacts on shallow marine macrofaunas are obscured by the incompleteness of shelf sections. We analyze mollusk assemblages bracketing (but not including) the PETM and find few notable lasting impacts on diversity, turnover, functional ecology, body size, or life history of important clades. Infaunal and chemosymbiotic taxa become more common, and body size and abundance drop in one clade, consistent with hypoxia-driven selection, but within-clade changes are not ...


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