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Full-Text Articles in Geochemistry

Quantifying Crustal Assimilation In Historical To Recent (1329-2005) Lavas At Mt. Etna, Italy: Insights From Thermodynamic Modeling, Marie Takach Jan 2018

Quantifying Crustal Assimilation In Historical To Recent (1329-2005) Lavas At Mt. Etna, Italy: Insights From Thermodynamic Modeling, Marie Takach

All Master's Theses

The nearly continuous volcanic eruption record at Mt. Etna dating back approximately 700 years provides an excellent opportunity to investigate the geochemical evolution of a highly active volcano. Of particular interest is elucidating the cause of a selective enrichment in alkali elements (K, Rb, Cs) and 87Sr/86Sr. This alkali enrichment trend, which began in the 17th century and accelerated after 1971, was accompanied by an increase in the volume, frequency, and explosivity of eruptions. To explain this enrichment, two major arguments are invoked: (1) crustal contributions (e.g., assimilation of the sedimentary basement), and (2) changes in …


Trace Metal And Metalloid Behavior In The Submicron Scale Components Of Coal Fly Ashes: Insights From Combined Microscopic And Microbiological Studies, Matthew Costa Jan 2018

Trace Metal And Metalloid Behavior In The Submicron Scale Components Of Coal Fly Ashes: Insights From Combined Microscopic And Microbiological Studies, Matthew Costa

Open Access Theses & Dissertations

For over a century, coal has been used worldwide to meet ever-growing energy demands. Coal combustion accounts for over 30% of electricity generation in the United States. In the U.S., coal combustion produces annually over 100 million tons of coal combustion products (CCPs) of which only 30% are used in beneficial and economic ways. One of the primary CCPs from coal-burning power plants is fly ash, typically fine-sized and enriched in many trace elements (e.g., arsenic, chromium, lead, and vanadium). When disposed in the environment, fly ash may release significant concentrations of trace elements into surrounding ecosystems and induce toxicity …


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 …


Spatial And Temporal Analysis Of Surface Water Quality In Relation To Marcellus Shale Gas Development In The Northern Panhandle Of West Virginia, Rachel Yesenchak Jan 2018

Spatial And Temporal Analysis Of Surface Water Quality In Relation To Marcellus Shale Gas Development In The Northern Panhandle Of West Virginia, Rachel Yesenchak

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pre-existing water chemistry data available from the West Virginia Department of Environmental Protection were used to examine temporal changes in surface water quality related to the onset of Marcellus Shale gas drilling activity in the state of West Virginia. Drilling is concentrated in the northwestern portion of the state. Watersheds were delineated for twelve discrete stream sampling locations in the Upper Ohio-Wheeling HUC-8 sub-basin, where shale gas drilling is prevalent. Kruskal-Wallis tests were deployed to compare pre- and post-drilling concentrations of conductivity, chloride, and total suspended solids for each location. Increased concentrations of these parameters are associated with surface water …


Occupational Seasonality And Paleoenvironmental Reconstruction At Quebrada Jaguay 280, Stephanie Melissa Gruver Jan 2018

Occupational Seasonality And Paleoenvironmental Reconstruction At Quebrada Jaguay 280, Stephanie Melissa Gruver

Graduate Research Theses & Dissertations

Quebrada Jaguay 280 (QJ-280) is one of the oldest maritime archaeological sites in the New World. Previous excavations of the southern Peruvian coastal site have dated occupation from ~13,000-8,000 cal yr BP. These excavations also determined that the occupants of the site used preferential maritime resource procurement strategies and had an interzonal connection to the highlands. In 2017 a new excavation was conducted at QJ-280 and the remains of the marine mollusk Mesodesma donacium were recovered. Geochemical examinations on the shell remains informed on the occupational seasonality of the site and reconstructed sea surface temperatures experienced off the coast of …


Photochemical Cycling Of Reactive Oxygen Species In Hydrothermal Systems: Impacts On Biosignature Preservation, Megan A. Mave Jan 2018

Photochemical Cycling Of Reactive Oxygen Species In Hydrothermal Systems: Impacts On Biosignature Preservation, Megan A. Mave

Graduate Student Theses, Dissertations, & Professional Papers

Life originated on early Earth, despite harsh, highly reducing conditions. Life may have also emerged on early Mars, when conditions on the two planets were similar (i.e. before atmosphere loss and desiccation). NASA’s 2020 Mars rover mission aims to identify biosignatures (i.e. evidence of life) in early Martian deposits. Potential exploration sites include extinct hydrothermal springs, due to their high habitability and preservation potential. This study aims to better understand biosignature preservation in hydrothermal systems analogous to those on early Mars (i.e. reducing and Fe-rich).

Reactive oxygen species (ROS) are highly reactive molecules formed primarily by photochemical reactions. ROS are …


Using Multiple Environmental Tracers To Investigate The Relative Role Of Soil And Deep Groundwater In Stream Water Generation For A Snow-Dominated Headwater Catchment, Isabellah V. Von Trapp Jan 2018

Using Multiple Environmental Tracers To Investigate The Relative Role Of Soil And Deep Groundwater In Stream Water Generation For A Snow-Dominated Headwater Catchment, Isabellah V. Von Trapp

Graduate Student Theses, Dissertations, & Professional Papers

In this study, seasonal fluctuation of environmental tracers in stream flow, soil water, and deep bedrock groundwater were used to constrain the role of deep bedrock groundwater in streamflow generation for a mountainous headwater catchment. Synoptic measurements of stream discharge, 222Rn, specific conductivity and major ion concentrations were measured throughout the water year over a 5 km reach of Cap Wallace Creek in the Lubrecht Experimental Forest, Montana, U.S.A. with the intention of understanding groundwater – surface water interactions across spatial and temporal scales. Stage measurements were continually recorded at seven stilling well locations along the reach. Discharge measurements …


Tuhualite In A Peralkaline Rhyolitic Ignimbrite From Pantelleria, Italy, Boguslaw Baginski, Ray Macdonald, John C. White, Lidia Jezak Jan 2018

Tuhualite In A Peralkaline Rhyolitic Ignimbrite From Pantelleria, Italy, Boguslaw Baginski, Ray Macdonald, John C. White, Lidia Jezak

EKU Faculty and Staff Scholarship

An occurrence of the rare mineral tuhualite (NaFe3+Fe2+Si6O15) is reported in a peralkaline rhyolitic ignimbrite from the 11 island of Pantelleria, Italy. The mineral formed during devitrification of glassy fiamme and varies in form from anhedral plates to 12 perfect euhedral in open vesicles. There is significant replacement of Fe2+ by Mn (FMQ in the presence of a 14 hydrous fluid.


Environmental Monitoring And Peat Assessment Using Multivariate Analysis Of Regional-Scale Geochemical Data, Jennifer M. Mckinley, Eric Grunsky, Ute Mueller Jan 2018

Environmental Monitoring And Peat Assessment Using Multivariate Analysis Of Regional-Scale Geochemical Data, Jennifer M. Mckinley, Eric Grunsky, Ute Mueller

Research outputs 2014 to 2021

A compositional multivariate approach was used to analyse regional-scale soil geochemical data obtained as part of the Tellus Project generated by the Geological Survey of Northern Ireland. The multi-element total concentration data presented comprise X-ray fluorescence (XRF) analyses of 6862 rural soil samples collected at 20-cm depth on a non-aligned grid at one site per 2km2" role="presentation">2km2. Censored data were imputed using published detection limits. Each soil sample site was assigned to the regional geology map, resulting in spatial data for one categorical variable and 35 continuous variables comprised of individual and amalgamated elements. This paper examines the extent …


Evaluation Of The Community Multiscale Air Quality Model For Simulating Winter Ozone Formation In The Uinta Basin, Rebecca Matichuk, Gail Tonnesen, Deborah Luecken, Rob Gillam, Sergey L. Napelenok, Kirk R. Baker, Donna Schwede, Ben Murphy, Detlev Helmig, Seth N. Lyman, Shawn Roselle Dec 2017

Evaluation Of The Community Multiscale Air Quality Model For Simulating Winter Ozone Formation In The Uinta Basin, Rebecca Matichuk, Gail Tonnesen, Deborah Luecken, Rob Gillam, Sergey L. Napelenok, Kirk R. Baker, Donna Schwede, Ben Murphy, Detlev Helmig, Seth N. Lyman, Shawn Roselle

Bingham Research Center

The Weather Research and Forecasting (WRF) and Community Multiscale Air Quality (CMAQ) models were used to simulate a 10 day high-ozone episode observed during the 2013 Uinta Basin Winter Ozone Study (UBWOS). The baseline model had a large negative bias when compared to ozone (O3) and volatile organic compound (VOC) measurements across the basin. Contrary to other wintertime Uinta Basin studies, predicted nitrogen oxides (NOx) were typically low compared to measurements. Increases to oil and gas VOC emissions resulted in O3 predictions closer to observations, and nighttime O3 improved when reducing the deposition velocity …


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 …


Phosphate Speleothems In Caves Developed In Iron Ores And Laterites Of The Carajás Mineral Province (Brazil) And A New Occurrence Of Spheniscidite, Alan R.L. Albuquerque, Rômulo S. Angélica, Daniele F. Gonçalves, Simone P.A. Paz Dec 2017

Phosphate Speleothems In Caves Developed In Iron Ores And Laterites Of The Carajás Mineral Province (Brazil) And A New Occurrence Of Spheniscidite, Alan R.L. Albuquerque, Rômulo S. Angélica, Daniele F. Gonçalves, Simone P.A. Paz

International Journal of Speleology

The Carajás Mineral Province has one of the largest concentrations of caves in Brazil, and its iron ore is among the country’s main exports. As a result of iron ore intense extraction, new environmental policies have been implemented. In an attempt to balance economic activity and environmental conservation, an inventory and a relevance-based classification of caves were implemented in 2008 as criteria for environmental licensing of mining ventures. This implementation motivated the present study of phosphate speleothems in Carajás’ caves developed in ferriferous rocks. The objectives of this study are to describe the phosphate minerals and their formation processes based …


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 …


Provenance Analysis Of The Grover Gravel Using Detrital Zircon Geochronology, Petrology And Heavy Mineral Analysis, Grant Spoering Dec 2017

Provenance Analysis Of The Grover Gravel Using Detrital Zircon Geochronology, Petrology And Heavy Mineral Analysis, Grant Spoering

Graduate Theses/Dissertations

The Grover Gravel in the St. Louis, Missouri area contains a mix of chert, quartzite, jasper, and ironstone in clast sizes ranging up to 60 cm. The gravel varies in thickness from a veneer to over 30 feet and rests on upland surfaces at elevations sometimes exceeding 300 feet above the floors of major valleys. A pre-Pleistocene age generally has been proposed or assumed for the gravel, which classically has been interpreted to be a meandering-stream deposit atop an extensive flat upland surface, which was subsequently eroded and dissected by rejuvenated streams. However, large quartzite boulders in the gravel also …


A Geochemical Investigation And Comparison Between Organic-Rich Black Shales And Mississippi Valley-Type Pb-Zn Ores In The Southern Ozarks Region, Bryan Michael Bottoms Dec 2017

A Geochemical Investigation And Comparison Between Organic-Rich Black Shales And Mississippi Valley-Type Pb-Zn Ores In The Southern Ozarks Region, Bryan Michael Bottoms

Graduate Theses and Dissertations

Mississippi Valley-type (MVT) deposits are base metal sulfide deposits that are important economic sources of both Pb and Zn, accounting for 24% of the global Pb and Zn reserves. They are found all over the world, often hosted in platform carbonates on the flanks of sedimentary basins, and often in proximity to hydrocarbons. They are epigenetic, not related to igneous activity, and thought to be sourced from low temperature, highly saline basinal brines that are expelled from sedimentary basins during compaction and/or in conjunction with an orogenic event. The basinal lithologies responsible for providing the metals for the ores are …


Cave Monitoring In The Béke And Baradla Caves (Northeastern Hungary): Implications For The Conditions For The Formation Cave Carbonates, György Czuppon, Attila Demény, Szabolcs Leél-Őssy, Mihály Óvari, Mihály Molnár, József Stieber, Klaudia Kiss, Krisztina Kármán, Gergely Surányi, László Haszpra Nov 2017

Cave Monitoring In The Béke And Baradla Caves (Northeastern Hungary): Implications For The Conditions For The Formation Cave Carbonates, György Czuppon, Attila Demény, Szabolcs Leél-Őssy, Mihály Óvari, Mihály Molnár, József Stieber, Klaudia Kiss, Krisztina Kármán, Gergely Surányi, László Haszpra

International Journal of Speleology

In order to use speleothems in the reconstruction of past climate and environmental changes it is necessary to understand the environmental and hydrological processes that determine the physico-chemical conditions of carbonate precipitation and hence speleothem formation. Therefore, in this study an extended monitoring program was conducted in the Béke and Baradla caves located in the Aggtelek region (Northeastern Hungary). The studied caves are rich in speleothem and flowstone occurrences with great potential for paleoclimatology studies. The monitoring activity included measurements of atmospheric and cave temperatures, CO2 concentration in cave air, as well as chemical and isotopic compositions of water …


U–Pb Dating Of Cave Spar: A New Shallow Crust Landscape Evolution Tool, D. D. Decker, V. J. Ployak, Y. Asmeron, Matthew Lachniet Nov 2017

U–Pb Dating Of Cave Spar: A New Shallow Crust Landscape Evolution Tool, D. D. Decker, V. J. Ployak, Y. Asmeron, Matthew Lachniet

Geoscience Faculty Research

In carbonate terranes, rocks types that provide apatite are not available to effectively use apatite fission track (AFT) or (U/Th)‐He chronometry (AHe). Here we suggest that calcite cave spar can be an effective chronometer and complimentary to AFT and AHe thermochronometers in carbonate regions such as our study area, the Guadalupe Mountains of southeastern New Mexico, and west Texas. Our measured depth of cave spar deposition is 500 ± 250 m beneath the regional water table, formed at temperatures of 40° to 80°C, indicating that these caves and their spar crystals form near the supercritical CO2‐subcritical CO2 boundary where we …


Resolving Chronological And Temperature Constraints On Antarctic Deglacial Evolution Through Improved Dating Methodology, Cristina Subt Nov 2017

Resolving Chronological And Temperature Constraints On Antarctic Deglacial Evolution Through Improved Dating Methodology, Cristina Subt

USF Tampa Graduate Theses and Dissertations

In order to determine the timing of Antarctic ice sheet retreat and advance during the Late Quaternary, various tools are used to measure the age of marginal marine sediments. Carbonate 14C dating is a well-established approach, but requires foraminiferal microfossils, shells or other carbonate materials that are rare in most Antarctic regions, and may also suffer from vital effects, which can result in variability of up to 500 years in living organisms. Bulk acid insoluble organic (AIO) 14C dates are frequently as an alternative, but this approach works best where high productivity and sedimentation rates reign, and not too well …


Paleoenvironmental Reconstruction Using Coral Microatolls (Sp. Siderastrea Siderea) From The Gulf Of Gonâve, Haiti, Gilman Reno Ouellette Jr. Nov 2017

Paleoenvironmental Reconstruction Using Coral Microatolls (Sp. Siderastrea Siderea) From The Gulf Of Gonâve, Haiti, Gilman Reno Ouellette Jr.

LSU Doctoral Dissertations

Natural and anthropogenic climate changes present unique and serious risks to society. In order to plan and implement adaptation and mitigation strategies successfully, regional manifestations of broad-scale climate changes must be understood robustly. The Caribbean region contains part of the Western Hemisphere Warm Pool (WHWP), a major sea surface temperature (SST) feature that plays a key role in North Atlantic climate. Climate variability in the Caribbean is captured poorly by climate models, due in part to a lack of continuous, multidecadal instrumental climate records from the region. I explored three research questions in this dissertation: Does non-systematic bias exist in …


Paleoenvironmental Variation And Provenance Records From Neogene Deep Sea Sediment Of The South China Sea, Chang Liu Nov 2017

Paleoenvironmental Variation And Provenance Records From Neogene Deep Sea Sediment Of The South China Sea, Chang Liu

LSU Doctoral Dissertations

I employed several paleoenvironmental proxies by utilizing deep sea sediment from the largest marginal basin in east Asia, namely the South China Sea (SCS), to reconstruct the long term paleoenvironmental variation in SE Asia since the Neogene. Sediments deposited within the SCS were mainly delivered by several major fluvial systems whose catchment basins cover several geological blocks in SE Asia. By analyzing the sediment’s geochemical and mineralogical characteristics, several indices which are affected by the source of the sedimentary influx, as well as the weathering state could be built and applied to constrain my paleoenvironmental reconstructions

Two deep sea drilling …


Geothermal Flux And Phreatic Speleogenesis In Gypsum, Halite, And Quartzite Rocks, Giovanni Badino Nov 2017

Geothermal Flux And Phreatic Speleogenesis In Gypsum, Halite, And Quartzite Rocks, Giovanni Badino

International Journal of Speleology

The first layers of rock underground are in thermal contact with the external atmosphere mainly through infiltrating meteoric water. This relatively cool zone absorbs rising geothermal energy, which heats the water. If the aquifer consists of gypsum, halite or quartzite, the water at those depths is usually salt-saturated, so the increase in temperature renders the water aggressive again. This in turn leads to rock dissolution and formation of phreatic conduits. This way, the geothermal flow creates caves that do not necessarily reach the surface. This paper analyzes the speed of the excavation, which, in different types of rocks, depends only …


When, How, And Why Did The West Antarctic Ice Sheet Retreat In The Ross Sea Since The Last Glacial Maximum Using Foraminiferal And Porewater Geochemistry, Matthew Decesare Nov 2017

When, How, And Why Did The West Antarctic Ice Sheet Retreat In The Ross Sea Since The Last Glacial Maximum Using Foraminiferal And Porewater Geochemistry, Matthew Decesare

LSU Doctoral Dissertations

The Antarctic Ice Sheets (AIS) began to retreat from their Last Glacial Maximum (LGM) position sometime after 19,000 years ago. However, the corrosive waters circulating around Antarctica has prevented the recovery of radiocarbon-dateable material, hindering the development of deglacial chronologies. During Expedition NBP1502B to the eastern Ross Sea, an unprecedented quantity of fossil foraminifera and bivalves were recovered. Radiocarbon-dated specimens have been used to constrain the timing of West-AIS retreat from Whales Deep basin and Ross Bank. Whales Deep samples show that the WAIS retreated from its LGM position on the continental shelf edge by 14,700 ± 400 calibrated radiocarbon …


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 …


A Geochemical And Petrological Analysis Of The San Rafael Volcanic Field, Utah, Danielle Koebli Nov 2017

A Geochemical And Petrological Analysis Of The San Rafael Volcanic Field, Utah, Danielle Koebli

USF Tampa Graduate Theses and Dissertations

The San Rafael Volcanic Field, Utah, is a 4.6 Ma extinct monogenetic field that is found in the Northern Transition Zone of the Colorado Plateau. The field has been eroded, leaving the dikes, conduits, and sills visible. Within the sills we see evidences of immiscibility in the form of an intermediate syenite (~50 wt% SiO2) enclosed in a mafic shonkinite (~48 wt % SiO2). Field relations indicate that sills were formed due to single events (Richardson et al., 2015), which makes in-situ differentiation the process at the origin of both rock types. Geochemical data supports differentiation …


Bonneville Basin Data, Larry V. Benson Nov 2017

Bonneville Basin Data, Larry V. Benson

United States Geological Survey: Datasets

In the Bonneville Basin folder, all data were reported in: Benson, L.V., Lund, S.P., Smoot, J.P., Rhode, D.E., Spencer, R.J., Verosub, K.L., Louderback, L.A., Johnson, C.A., Rye, R.O., Negrini, R., 2011. The rise and fall of Lake Bonneville between 45 and 10.5 ka. Quaternary International 235: 57-69.

http://digitalcommons.unl.edu/usgsstaffpub/726

General Comment: in most cases an age model based on 14C analyses is not included with the data sets although ones were created for the original publications. Given the general problems with 14C ages in the lakes of the Great Basin, age models based on paleomagnetic secular variation (PSV) are …


Groundwater And Subsurface Water In A Landscape With Shallow Bedrock: Implications For Agricultural Nutrient Export, Laura Kelley, Hunter R. Evans, Reid E. Buskirk, Jonathan M. Malzone, Walter S. Borowski Nov 2017

Groundwater And Subsurface Water In A Landscape With Shallow Bedrock: Implications For Agricultural Nutrient Export, Laura Kelley, Hunter R. Evans, Reid E. Buskirk, Jonathan M. Malzone, Walter S. Borowski

EKU Faculty and Staff Scholarship

Controls on nutrient export from agricultural landscapes include regional hydrological and geological conditions. In many central Kentucky basins shallow fractured bedrock produces focused groundwater discharge and flashy runoff events. Eastern Kentucky University’s Meadowbrook Farm is currently experimenting with nutrient sequestration techniques; however the effectiveness of these techniques given the local hydrogeology needs to be quantified. Our objective was to determine the potential pathways for nutrient export by mapping key hydrologic features and using a watershed approach. The key features mapped were springs, tile drains, runoff channels, land use and the underlying geology. We chose a 0.46 km2 watershed to …


Geochemical Characteristics And Storm Dynamics Of Surface Waters And Groundwater At Eastern Kentucky University’S Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone Nov 2017

Geochemical Characteristics And Storm Dynamics Of Surface Waters And Groundwater At Eastern Kentucky University’S Meadowbrook Farm, Madison County, Kentucky, Reid E. Buskirk, Walter S. Borowski, Jonathan M. Malzone

EKU Faculty and Staff Scholarship

Agricultural activities often contaminate watersheds with excess nutrients leading to poor water quality and eutrophication. Eastern Kentucky University’s Meadowbrook Farm raises crops and livestock, contributing dissolved nutrients to the neighboring Muddy Creek watershed. Consequently, the Farm is developing methods to sequester and limit nutrient contamination.

Before phosphorous sequestration methods can be tested, the geochemistry of surface water and groundwater on the Farm need to be better understood to determine hydrological pathways. We use naturally-occurring, dissolved cations as tracers to identify the contribution of different water sources and interpret storm events.

Water samples taken from springs (groundwater), surface water, and storm …


Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker Oct 2017

Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker

Publications and Research

The authors have previously published an article at the 2004 Geological Society of America Annual Meeting, Petrogenetic Significance of Garnets in the Bedrock of New York City, in which they suggested that the garnet xenocrysts observed in the quartzofeldspathic zones of the migmatites, so frequently seen both at the surface, and below the surface pursuant to the construction of the Manhattan portion of New york City Water Tunnel #3, were a refractory residue of the anatectic melting of the immediately surrounding schistose bedrock. Although the relatively high melting point temperature of garnet compared to other minerals in the surrounding …


Diurnal And Seasonal Variation In Groundwater Nitrate -N Concentration In A Saturated Buffer Zone, Joseph Miller Oct 2017

Diurnal And Seasonal Variation In Groundwater Nitrate -N Concentration In A Saturated Buffer Zone, Joseph Miller

Theses and Dissertations

Surface water pollution by nitrate (NO3-) is identified as a critical problem in agricultural land-use areas. Excess NO3- loading causes eutrophication and hypoxia in near-shore marine waters such as the Gulf of Mexico. Diversion of agricultural runoff into saturated buffer zones reduces NO3- loading. Although the mechanisms responsible for NO3- reduction in saturated buffer zones are well characterized, little is known about how NO3- concentrations vary temporally and what factors control those changes. The objective of this study is to understand NO3- concentration and environmental factor variability in a saturated buffer zone on a diurnal scale within and among the …


A Near-Global Atmospheric Distribution Of N2o Isotopologues, Peter F. Bernath, Mahdi Yousefi, Eric Buzan, Chris D. Boone Oct 2017

A Near-Global Atmospheric Distribution Of N2o Isotopologues, Peter F. Bernath, Mahdi Yousefi, Eric Buzan, Chris D. Boone

Chemistry & Biochemistry Faculty Publications

The distributions of the four most abundant isotopologues and isotopomers (N2O, 15NNO, N15NO, and NN18O of nitrous oxide have been measured in the Earth's stratosphere by infrared remote sensing with the Atmospheric Chemistry Experiment (ACE) Fourier transform spectrometer. These satellite observations have provided a near-global picture of N2O isotopic fractionation. The relative abundances of the heavier species increase with altitude and with latitude in the stratosphere as the air becomes older. The heavy isotopologues are enriched by 20-30% in the upper stratosphere and even more over the poles. These observations are …