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Articles 121 - 150 of 274

Full-Text Articles in Geochemistry

Elevated Black Carbon Concentrations And Atmospheric Pollution Around Singrauli Coal-Fired Thermal Power Plants (India) Using Ground And Satellite Data, Ramesh Singh, Sarvan Kumar, Abhay K. Singh Nov 2018

Elevated Black Carbon Concentrations And Atmospheric Pollution Around Singrauli Coal-Fired Thermal Power Plants (India) Using Ground And Satellite Data, Ramesh Singh, Sarvan Kumar, Abhay K. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

The tropospheric NO2 concentration from OMI AURA always shows high concentrations of NO2 at a few locations in India, one of the high concentrations of NO2 hotspots is associated with the locations of seven coal-fired Thermal Power plants (TPPs) in Singrauli. Emissions from TPPs are among the major sources of black carbon (BC) soot in the atmosphere. Knowledge of BC emissions from TPPs is important in characterizing regional carbonaceous particulate emissions, understanding the fog/haze/smog formation, evaluating regional climate forcing, modeling aerosol optical parameters and concentrations of black carbon, and evaluating human health. Furthermore, elevated BC concentrations, over the …


Groundwater Contamination At Coal Ash Deposit Sites In Kentucky, Brandon Rose Nov 2018

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

Scholars Week

No abstract provided.


Indirect Greenhouse Gas Dynamics In Karst Groundwater Systems Under Agricultural Land Use, Stacy Wayne Antle Oct 2018

Indirect Greenhouse Gas Dynamics In Karst Groundwater Systems Under Agricultural Land Use, Stacy Wayne Antle

Masters Theses & Specialist Projects

Greenhouse gases (GHGs) are a major global environmental concern, because their concentrations have continuously increased over the past few centuries, due to global population growth, fossil fuel dependency, and the Industrial Revolution. Since these gases are naturally occurring phenomena, they will never be completely eliminated. Efforts to reduce them span numerous scientific attempts, with minimal improvements in reducing their atmospheric concentrations. In agricultural land practices, greenhouse gases are common byproducts that affect the atmosphere and, potentially, the groundwater where livestock and fertilizers are key contributors. Little is known about the fate of such greenhouse gases in dissolved form, known as …


Regulation Of Dissolved Arsenic Using Zero-Valent Iron With Gypsum And Sulfate Reducing Bacteria: Laboratory Microcosm And Column Studies, Ying Liu Sep 2018

Regulation Of Dissolved Arsenic Using Zero-Valent Iron With Gypsum And Sulfate Reducing Bacteria: Laboratory Microcosm And Column Studies, Ying Liu

Dissertations, Theses, and Capstone Projects

Bench scale microcosm incubation was first conducted in two stages to examine the removal of arsenic (As) by zero-valent iron (ZVI) in the presence of sulfate reducing bacteria, gypsum as well as organic substrates under anaerobic condition. About 98% of dissolved As was removed from solution within 20 days with concurrent decrease of dissolved sulfate and growth of bacterial population. Mineralogy analysis using SEM-EDS found the formation of iron sulfide and Fourier-transformed infrared (FTIR) spectroscopy analysis indicates that some As is associated with pyrite. The main iron corrosion product was found as ferrihydrite with traces of lepidocrocite. Sequential leaching shows …


Geotraces And Beyond: Studies Of Trace Elements In Coastal And Open Ocean Waters With An Emphasis On The Effects Of Oxygen Depletion And Hydrothermal Plumes, Peng Ho Aug 2018

Geotraces And Beyond: Studies Of Trace Elements In Coastal And Open Ocean Waters With An Emphasis On The Effects Of Oxygen Depletion And Hydrothermal Plumes, Peng Ho

Dissertations

We investigated various dissolved trace element (dTE) distributions in two distinct areas: the coastal northern Gulf of Mexico and the eastern tropical Pacific Ocean.

A multi-year (2007‒2011) chemical time series of eight stations in the western Mississippi Sound (MS) and northwestern Mississippi Bight (MB) was undertaken to examine the factors affecting chemical distributions in this dynamic region. Key findings include the frequent development of bottom water hypoxia in MB during late spring-summer, the likely contribution of submarine groundwater discharge (SGD) to the material flows, and observation of effects of episodic events including tropical storms and the opening of the Bonnet …


Spatial And Temporal Trends Of Mining-Related Lead-Zinc Sediment Contamination, Galena River Watershed, Sw Wisconsin-Nw Illinois, Dylan Alexander King Aug 2018

Spatial And Temporal Trends Of Mining-Related Lead-Zinc Sediment Contamination, Galena River Watershed, Sw Wisconsin-Nw Illinois, Dylan Alexander King

Graduate Theses/Dissertations

Alluvial sediments within the Galena River Watershed were severely contaminated with heavy metals by historical zinc (Zn) and lead (Pb) mining operations during the early 1800s until 1979. Since the mines closed, there have been efforts to remediate on-site mine waste. However, the effectiveness of these efforts to reduce metal concentrations in stream sediments is unknown. This study compares present-day (2017) contamination trends in the Galena River Watershed to trends reported 25 years ago. A total of 415 sediment/soil samples were collected and analyzed using X-ray florescence spectrometry to determine sediment metal concentrations. The highest concentrations of zinc measured were …


Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman Jul 2018

Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman

Numeracy

Timothy H. Dixon. 2017. Curbing Catastrophe: Natural Hazards and Risk Reduction in the Modern World. (New York, NY: Cambridge University Press) 300 pp. ISBN 978-1108113663.

In Curbing Catastrophe, Timothy H. Dixon explores commonalities among natural disasters like Hurricane Katrina, the 2010 earthquake in Haiti, and the meltdown at Fukushima. He identifies communication failure between scientists and policy makers as a major culprit in the devastation that results from such events and offers strategies for improving that communication. He includes optional in-depth scientific and quantitative examinations of the events and the resulting devastation, making the book appropriate for use …


Predicting Spatial Patterns In Precipitation Isotope (Δ2h And Δ18o) Seasonality Using Sinusoidal Isoscapes, Scott T. Allen, James W. Kirchner, Gregory R. Goldsmith May 2018

Predicting Spatial Patterns In Precipitation Isotope (Δ2h And Δ18o) Seasonality Using Sinusoidal Isoscapes, Scott T. Allen, James W. Kirchner, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding how precipitation isotopes vary spatially and temporally is important for tracer applications. We tested how well month‐to‐month variations in precipitation δ18O and δ2H were captured by sinusoidal cycles, and how well spatial variations in these seasonal cycles could be predicted, across Switzerland. Sine functions representing seasonal cycles in precipitation isotopes explained between 47% and 94% of the variance in monthly δ18O and δ2H values at each monitoring site. A significant sinusoidal cycle was also observed in line‐conditioned excess. We interpolated the amplitudes, phases, and offsets of these sine functions across the landscape, using multiple linear …


An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan Apr 2018

An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study considers the various factors that regulate nutrients supply in the Red Sea. Multi-sensor observation and reanalysis datasets are used to examine the relationships among dust deposition, sea surface temperature (SST), and wind speed, as they may contribute to anomalous phytoplankton blooms, through time-series and correlation analyses. A positive correlation was found at 0–3 months lag between chlorophyll-a (Chl-a) anomalies and dust anomalies over the Red Sea regions. Dust deposition process was further examined with dust aerosols’ vertical distribution using satellite lidar data. Conversely, a negative correlation was found at 0–3 months lag between SST anomalies …


Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga Apr 2018

Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga

Masters Theses & Specialist Projects

An investigation into the carbon dynamics and weathering processes occurring in Icelandic glacial-fed streams was conducted during the spring to summer seasonal transition in June of 2017. Four major outlet rives were sampled from the glaciers of Gígjökull, Steinsholtsjökull, Sólheimajökull, and Falljökull. Markarfljót, the major river that Gígjökull, Steinsholtsjökull, and many other glaciers drain into, was also sampled. Longitudinal sampling occurred at all sites to capture downstream trends in the hydrogeochemistry and carbon dynamics. Distinct differences in geochemistry between glacier surface meltwater, sub-glacial waters, pro-glacial lake water, and post-mixed downstream samples were evident in the data. Glacier surface streams were …


Nutrient Export From A Proximal Intermittent Stream Draining Eku Meadowbrook Farm, Madison County, Kentucky, James Scott Winter, Walter S. Borowski, Jonathan M. Malzone Mar 2018

Nutrient Export From A Proximal Intermittent Stream Draining Eku Meadowbrook Farm, Madison County, Kentucky, James Scott Winter, Walter S. Borowski, Jonathan M. Malzone

EKU Faculty and Staff Scholarship

Agricultural activities contribute significant amounts of nutrients that contaminate surface and subsurface water. Eastern Kentucky University (EKU) Meadowbrook Farm (Madison County, Kentucky) seeks to decrease its export of nutrients to Muddy Creek using sequestration techniques. The first step in the overall process is to determine nutrient export at present, before sequestration efforts take place. Here we estimate the export of phosphate, nitrate, and ammonium during Tropical Storm Cindy (July 22 to 24, 2017) from a proximal, intermittent stream, named the BRC. This stream drains a representative portion the Farm, receiving water from a dairy complex, pasture, and cropland.

To estimate …


Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops Feb 2018

Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops

School of Biological Sciences: Faculty Publications

Global change-induced litter decomposition strongly affects the carbon (C) and nitrogen (N) dynamics in grassland ecosystems. However, few studies show the interactive effects of global change factors on litter and root decomposition. We conducted a four-year grassland field experiment to examine the quality and decomposition of litter and root in a three-factorial experiment with elevated CO2, increased N deposition, and plant species richness. We found that elevated CO2 decreased the litter N content and root lignin content. N addition increased the root N content and decreased the litter lignin content. Increasing plant richness decreased the N and …


Nitrogen Isotopes Suggest A Change In Nitrogen Dynamics Between The Late Pleistocene And Modern Time In Yukon, Canada, Farnoush Tahmasebi, Fred J. Longstaffe, Grant Zazula Jan 2018

Nitrogen Isotopes Suggest A Change In Nitrogen Dynamics Between The Late Pleistocene And Modern Time In Yukon, Canada, Farnoush Tahmasebi, Fred J. Longstaffe, Grant Zazula

Earth Sciences Publications

A magnificent repository of Late Pleistocene terrestrial megafauna fossils is contained in ice-rich loess deposits of Alaska and Yukon, collectively eastern Beringia. The stable carbon (δ13C) and nitrogen (δ15N) isotope compositions of bone collagen from these fossils are routinely used to determine paleodiet and reconstruct the paleoecosystem. This approach requires consideration of changes in C- and N-isotope dynamics over time and their effects on the terrestrial vegetation isotopic baseline. To test for such changes between the Late Pleistocene and modern time, we compared δ13C and δ15N for vegetation and bone …


Environmental Forensics Study Of Crude Oil And Petroleum Product Spills In Coastal And Oilfield Settings: Combined Insights From Conventional Gc-Ms, Thermodesorption-Gc-Ms And Pyrolysis-Gc-Ms, Michael A. Kruge, José Luis Gallego, Azucena Lara-Gonzalo, Noemi Esquinas Jan 2018

Environmental Forensics Study Of Crude Oil And Petroleum Product Spills In Coastal And Oilfield Settings: Combined Insights From Conventional Gc-Ms, Thermodesorption-Gc-Ms And Pyrolysis-Gc-Ms, Michael A. Kruge, José Luis Gallego, Azucena Lara-Gonzalo, Noemi Esquinas

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

A representative set of five oil spill samples from four different regions displayed different product characteristics and different levels of weathering. Three of them were taken along shorelines affected by marine oil spill events, viz., Aboño and Prestige (Spain) and Deepwater Horizon (USA) and the other two were taken at inland oil spill sites (Angola and Kuwait). A multi-faceted environmental forensics approach revealed key molecular features. In addition to the conventional GC/MS analysis of saturated and aromatic fractions, the polar fractions also were analyzed, revealing a complex series of linear alkanones in those oil samples particularly enriched in aliphatics. Thermodesorption-GC-MS …


Stable Bromine Isotope Signature Of Bromoform From Enzymatic And Abiotic Formation Pathways And Its Application In Identifying Sources Of Environmental Bromoform In The Damariscotta River, Chengyang Wang Jan 2018

Stable Bromine Isotope Signature Of Bromoform From Enzymatic And Abiotic Formation Pathways And Its Application In Identifying Sources Of Environmental Bromoform In The Damariscotta River, Chengyang Wang

Honors Theses

Bromoform is a major source of atmospheric bromine. Most bromoform is produced by marine organisms including macroalgae and phytoplankton, using the enzyme bromoperoxidase (BPO). Bromoform can also be a byproduct of industrial processes such as water disinfection. Identifying sources of environmental bromoform is still a challenge. A novel technique of using quadrupole mass spectrometry coupled to a gas chromatography (GCqMS) was developed and optimized for Br isotope analyses. The study shows that GCqMS in single ion monitoring (SIM) mode can measure 81Br with precision of around ±0.7‰ (60pmol bromoform injected). This study aims to investigate stable Br isotopes of bromoform …


Abandoned Mine Land Impacts On Tributaries In The Upper Yakima River Watershed, Eastern Cascades, Washington, Scott Kugel Jan 2018

Abandoned Mine Land Impacts On Tributaries In The Upper Yakima River Watershed, Eastern Cascades, Washington, Scott Kugel

All Master's Theses

Effluent from abandoned mine lands (AMLs) in several drainages in Washington’s Eastern Cascades flows into the Yakima River. Similar sites in Idaho and Colorado are known producers of heavy metals and acid mine drainage. I determined the effects of nine AMLs on water quality in four tributaries to the Yakima River. Archival work was conducted to determine sites that were mined and contained a mill. Each site was characterized by physical features. Water and sediment samples were collected above, at, and below each AML. Samples were analyzed for pH and heavy metal content, and evaluated to determine if the AMLs …


A Combined Field, Experimental And Modeling Approach To Understand The Impacts Of Flood Irrigation On Pedogenic Caco3 And Co2 Dynamics In Drylands, Anna Cristina Ortiz Jan 2018

A Combined Field, Experimental And Modeling Approach To Understand The Impacts Of Flood Irrigation On Pedogenic Caco3 And Co2 Dynamics In Drylands, Anna Cristina Ortiz

Open Access Theses & Dissertations

Soil salinization is a global problem affecting 10% of agricultural soils, particularly in irrigated arid-lands. This study investigated salt loading through flood-irrigation, particularly of calcite (CaCO3) salt in the southwest of the United States. To evaluate the impact that flood-irrigation has on CaCO3 buildup and its effect on C-cycling, a natural soil and two agricultural soils were sampled: a pecan orchard and an alfalfa field in the El Paso, TX region. Agricultural soils in this study are flood irrigated by the Rio Grande river and by ground waters in its absence, both of which are oversaturated with calcite.

To trace …


Abiotic- And Biotic-Formation Of Manganese Oxides And Their Fate In Environmental Systems, Haesung Jung Dec 2017

Abiotic- And Biotic-Formation Of Manganese Oxides And Their Fate In Environmental Systems, Haesung Jung

McKelvey School of Engineering Graduate Student Theses & Dissertations

Manganese (hydr)oxide (Mn (hydr)oxide) minerals are ubiquitous in aquatic and terrestrial environments. These minerals have high surface areas and are highly sorptive and redox active. From decades of accumulated knowledge about natural redox cycling, we have found that Mn (hydr)oxides play critical roles as electron donors and acceptors in elemental geochemical cycling and biological metabolisms in nature. Thus, Mn (hydr)oxides have garnered increasing interest to understand natural systems. Considering the variety of redox reactions with Mn (hydr)oxides in nature, it is also expected that there should be diverse pathways to form Mn (hydr)oxides through abiotic and biotic processes. Previous studies …


Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard Dec 2017

Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard

Electronic Theses and Dissertations

ABSTRACT

Differential dissolution of gypsum karst within the Delaware Basin poses a significant threat to infrastructure that society depends on. The study area is located in Culberson County, Texas and traverses a distance of approximately 54 kilometers along RM 652 within the Gypsum Plain which is situated on the northern margin of the Chihuahua Desert and includes outcrops of Castile and Rustler strata that host karst geohazards. Regions of karst geohazard potential have been physically surveyed proximal to the study area in evaporites throughout the Castile Formation outcrop; minimal hazards, in comparison to the Castile Formation, have been documented in …


The Role Of High-Elevation Headwater Runoff In Streamflow Generation And Water Supply In The Northern Andes, Colombia, Laura Lotero Lozano Nov 2017

The Role Of High-Elevation Headwater Runoff In Streamflow Generation And Water Supply In The Northern Andes, Colombia, Laura Lotero Lozano

USF Tampa Graduate Theses and Dissertations

Water security requires that sufficient quantities of water be available at critical times. This is particularly challenging for high-intensity urban and agricultural settings. In underdeveloped nations, streamflow is commonly the preferred water source, as it is readily available and delivered cost-free to users. Yet, the sources of these critical streamflows are often unknown. This issue is salient in the Northern Andes, where basic knowledge of controlling factors for the quantity, quality, and timing of runoff is lacking. High-elevation headwaters are the primary catchment areas in the Northern Andes, but the extent of water providing to municipalities in the Northern Andes …


Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby Jul 2017

Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby

Adam Liska Papers

Many people tend to think that the outcome of any nuclear weapons use today will result in an escalatory situation with apocalyptic outcomes for the countries involved. Yet many factors are increasing the probability of the limited use of nuclear weapons (e.g., 1 to 20 warheads) in a range of conflict scenarios. Previous atmospheric model simulations of regional nuclear conflicts employing many relatively small bombs have been estimated to cause a global “nuclear autumn,” with great reductions in agricultural productivity, stratospheric ozone loss, and spread of hazardous radioactive fallout. The totality of these effects would result in widespread damage …


Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, Autumn B. Singer Jul 2017

Measuring Inorganic Carbon Fluxes From Carbonate Mineral Weathering From Large River Basins: The Ohio River Basin, Autumn B. Singer

Masters Theses & Specialist Projects

Rising atmospheric CO2 concentrations have motivated efforts to better quantify reservoirs and fluxes of Earth’s carbon. Of these fluxes from the atmosphere, one that has received relatively little attention is the atmospheric carbon sink associated with carbonate mineral dissolution. Osterhoudt (2014) and Salley (2016) explored new normalization techniques to improve and standardize a process for measuring this flux over large river basins. The present research extends this work to the 490,600 km2 Ohio River drainage basin and 11 subbasins. The study estimated the DIC flux leaving these basins between October 1, 2013, and September 30, 2014, based on secondary hydrogeochemical, …


Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca Jun 2017

Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca

Civil Engineering ETDs

Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes. …


Stable Isotope Investigation Of The Migratory Behavior Of Silverhaired Bats (Lasionycteris Noctivagans) In Eastern North America, Erin E. Fraser, Darin Brooks, Fred J. Longstaffe Jan 2017

Stable Isotope Investigation Of The Migratory Behavior Of Silverhaired Bats (Lasionycteris Noctivagans) In Eastern North America, Erin E. Fraser, Darin Brooks, Fred J. Longstaffe

Earth Sciences Publications

We investigated the migratory movements of silver-haired bats (Lasionycteris noctivagans) across the eastern extent of the species’ range. We conducted stable hydrogen isotope analysis of fur samples (δ2Hfur) from museum specimens collected across latitudes and at all times of the year. We first used these data to estimate the timing of fur replacement and to develop a model associating δ2Hfur with that of local precipitation (δ2Hprecip) at the location where fur replacement occurred. We then used this model to 1) identify individuals that had migrated …


Using 210po/210pb Disequilibria To Characterize The Biogeochemistry And Quantify The Dynamics Of Sea Ice In The Arctic, Katherine Denise Krupp Jan 2017

Using 210po/210pb Disequilibria To Characterize The Biogeochemistry And Quantify The Dynamics Of Sea Ice In The Arctic, Katherine Denise Krupp

Wayne State University Theses

Understanding the biogeochemical cycles of the Arctic Ocean is highly significant due to its many unique characteristics which impact the cycling of important trace elements, isotopes, and nutrients. Furthermore, with its seasonally-changing sea ice extent and substantial role in the global radiation balance, the Arctic is considered a sensitive indicator of global change. The study of 210Po and 210Pb disequilibria is used to determine 1) the residence time of ice-rafted sediments in sea ice, 2) ice floe dynamics such as ice accumulation rates, and 3) biogeochemical characterization of the Arctic due to the natural occurrence and particle reactivity of 210Po …


Gypsum, Calcite, And Dolomite Caprock Fabrics And Geochemistry From The Gypsum Valley Salt Diapir, Paradox Basin, Southwestern Colorado, Kevin Lerer Jan 2017

Gypsum, Calcite, And Dolomite Caprock Fabrics And Geochemistry From The Gypsum Valley Salt Diapir, Paradox Basin, Southwestern Colorado, Kevin Lerer

Open Access Theses & Dissertations

Caprocks are found on top of or in a lateral position relative to salt diapirs. The caprocks predominantly comprise sulfate minerals such as anhydrite or gypsum, which presumably accreted during the dissolution of salt from evaporite sediments. In some cases, the sulfate minerals are replaced by carbonate minerals, referred to as "carbonate caprock". Carbonate caprocks associated with salt diapirs are important because they can act as reservoirs or conduits for hydrocarbons, and because they can be easily misidentified as carbonate lithologies belonging to the stratigraphy of the sedimentary sequences adjacent to the diapir, which can jeopardize the accurate interpretation of …


Genesis Of Unique Carbonate Fans In A Pre-Salt Reservoir Analogue, Indio Mountains, West Texas, Andre Llanos Jan 2017

Genesis Of Unique Carbonate Fans In A Pre-Salt Reservoir Analogue, Indio Mountains, West Texas, Andre Llanos

Open Access Theses & Dissertations

Hydrocarbon exploration in pre-salt sediments of rift basins on the South Atlantic Margin have proven to be successful major oil plays. Located on the western margin of the rift, the Brazilian pre-salt reservoirs of the Santos, Campos, and Espirito Santo Basins are hosted by lacustrine/marine-influenced carbonates that comprise laterally extensive, laminated microbialite facies. The Indio Mountains, located in West Texas, provide well-exposed outcrops of Lower Cretaceous marine and non-marine rift basin strata that can be considered a reservoir-analog to the South Atlantic Margin pre-salt facies. Of particular interest for hydrocarbon exploration are unique carbonate features that have been discovered in …


Stratigraphic, Geochemical, And Geochronological Analysis Of The Wolfcamp-D Interval, Midland Basin, Texas, Zachary S. Perlman Jan 2017

Stratigraphic, Geochemical, And Geochronological Analysis Of The Wolfcamp-D Interval, Midland Basin, Texas, Zachary S. Perlman

Theses and Dissertations--Earth and Environmental Sciences

Subsurface data derived from ~388 ft of drill core from Martin County (TX) were used to understand the depositional setting of the Wolfcamp-D, a petroleum producing interval in the Midland Basin. Elemental geochemistry collected via x-ray fluorescence revealed a highly variable depositional history marked by the deposition of diverse siliciclastic and carbonate lithofacies. Integration of multiple datasets resulted in the interpretation of nine lithofacies, whose deposition appears cyclical. Correlations between molybdenum and total organic carbon indicate slow recharge of bottom waters and anoxic/euxinicconditions within the basin. The presence of phosphatic nodules coinciding with siliceous black mudrocks suggested high levels of …


Dam Removal In The Usa: Effects On River Water Quality, Michael A. Kruge Jan 2017

Dam Removal In The Usa: Effects On River Water Quality, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Dam removal decisions should ideally be made after a thorough cost-benefit analysis. If dam obsolescence, structural safety, harm to fisheries, maintenance costs, and reservoir eutrophication are among the primary concerns, decommissioning would likely be favored. On the other hand, dams provide considerable benefits including water storage for agricultural and urban consumption, renewable electricity generation, support of navigational canal systems, flood control, and lakes for recreation. Because of these competing factors and interests, dam removal decision-making in the United States is often a slow process fraught with controversy, as in the case of the Klamath River.

Dams provided mechanical water power …


Tracing Anthropogenic Salinity Inputs To The Semi-Arid Rio Grande River: A Multi-Isotope Tracer Approach, Sandra Garcia Jan 2017

Tracing Anthropogenic Salinity Inputs To The Semi-Arid Rio Grande River: A Multi-Isotope Tracer Approach, Sandra Garcia

Open Access Theses & Dissertations

Water is an important component for life and as such water quality and availability are major concerns in the world today. In arid to semi-arid regions, freshwater quality is especially important due to its scarcity. Elevated salinity of rivers in arid regions poses potentially devastating consequences for the communities that depend on these rivers as a source of freshwater. In the Rio Grande region, high salinity has led to severe reductions in crop productivity and accumulation of salts in soils. Salinity inputs into the river may come from both anthropogenic and natural sources. Thus, identifying and quantifying salinity inputs to …