Geochemistry Commons^™

Interpretation Of Hydrogeologic Data To Support Groundwater Management, Bazile Groundwater Management Area, Northeast Nebraska, 2019—A Case Demonstration Of The Nebraska Geocloud, Christopher M. Hobza, Gregory V. Steele

United States Geological Survey: Publications

Nitrate, age tracer, and continuous groundwater-level data were interpreted in conjunction with airborne electromagnetic (AEM) survey data to understand the movement of nitrate within the Bazile Groundwater Management Area (BGMA) in northeastern Nebraska. Previously published age tracer data and nitrate data indicated vertical stratification of groundwater quality. Younger groundwater sampled within shallow parts of the aquifer had higher concentrations of nitrate, with 70 percent exceeding the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter. In contrast, groundwater sampled from deeper parts of the aquifer indicated that nitrate concentrations were less than 2 milligrams per liter and …

The Persistence Of Acid Mine Drainage At An East Texas Coal Mine, Sarah Zagurski

Electronic Theses and Dissertations

The objective of this study was to estimate the time it will take for acid forming materials (pyrite) to be weathered to a state of equilibrium and thus cease to produce acid in ground and surface waters within Oak Hill Mine. This was accomplished using an ex-situ kinetic leaching study incorporating a humidity cell in a controlled laboratory setting. Leaching was conducted on soil cores obtained from the vadose zone at Oak Hill Mine and the humidity cell was used to accelerate oxidation of the pyrite within the cores.

An in-situ field study was also conducted that monitored groundwater conditions …

Raman Spectroscopic Investigation Of The Speciation Of Uranyl (Vi) And Thorium (Iv) Ions In Chloride-Bearing Aqueous Solutions Under Hydrothermal Conditions, Nadib Akram

Graduate Theses/Dissertations

Raman spectra were acquired for a uranyl chloride aqueous solution at temperatures ranging from 25°C to 500°C at the chloride concentration of 6M and uranium (vi) concentration of 0.05M. The measurements were taken by sealing the sample in a hydrothermal diamond anvil cell (HDAC) which enabled spectra acquisition at non-ambient conditions. The pressure inside the cell was measured by estimating the liquid-vapor homogenization temperature (T_H) and using the isochoric equation of state diagram of water. The acquired spectra were then fitted to determine the speciation distribution of the various uranyl chloride species for the mentioned concentration. The developed …

Sodium-Calcium Ratios In The Planktic Foraminifera Trilobatus Sacculifer As A Proxy For Sea Surface Salinity, Colton Steele Watkins

OES Theses and Dissertations

Recent culture and field studies have found a significant positive correlation between seawater salinity and the incorporation of sodium into foraminiferal calcite, suggesting a potential new proxy for reconstructing past changes in sea surface salinity (SSS) (Mezger et al., 2016 and Bertlich et al., 2018). In order to test the applicability of this new proxy in an open-ocean setting, Na/Ca ratios in the planktic foraminifera Trilobatus sacculifer (T. sacculifer Na/Ca) were measured from a suite of sediment core tops spanning a natural salinity gradient from the North Atlantic subtropical gyre to the South Atlantic subtropical gyre. Initial results from …

Microbe-Mineral Interactions During Exceptional Fossil Preservation, Stromatolite Formation, And Desert Varnish Growth, Michael Strange

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Ediacaran to Cambrian Deep Spring Formation consists of mixed carbonate-siliciclastic strata which contain an increasingly complex and biogeographically important biota. Past investigations of the Deep Spring Formation at Mt. Dunfee, Nevada, explored the highly diverse microbialite reefs consisting of a wide range of stromatolite morphologies which exerted significant control on local sedimentation and topography. Early investigations also documented the biomineralizing metazoan Cloudina (an Ediacaran index fossil). However, recent exploration of the area has resulted in the discovery of several new metazoan fossil communities consisting of a diverse assemblage of Ediacaran soft-tissue tubicolous vermiforms (tube fossils) similar to Cloudina. The …

Boron Adsorption In Clay Minerals: Implications For Martian Groundwater Chemistry And Prebiotic Processes, Matthew A. Nellessen, Laura Crossey, Patrick J. Gasda, Horton Newsom, Abdulmehdi Ali, Eric J. Peterson, Nina Lanza, Adriana Reyes-Newell, Dorothea Delapp, Chris Yeager, Andrea Labouriau, Roger C. Wiens, Samuel Clegg, Shelbie Legett, Debarati Das

Earth and Planetary Sciences ETDs

Boron has been detected on Mars [Gasda et al., 2017, Das et al., 2019, 2020] within calciumsulfate veins found within clay-rich rocks on Mars by the Mars Science Laboratory (MSL) rover using Laser Induced Breakdown Spectroscopy (LIBS) analysis. Boron plays a vital role in stabilizing ribose on Earth and has been suggested as a key requirement for life [Scorei et al., 2006, 2012; Furukawa et al., 2013, 2017; Becker et al., 2019]. Additionally, boron readily adsorbs to phyllosilicate clay minerals and is often associated with biologic processes in clay soils. The discovery of boron on Mars in proximity to phyllosilicate …

What Martian Meteorites Reveal About The Interior And Surface Of Mars, Arya Udry, G. H. Howarth, C. D.K. Herd, J. M.D. Day, T. J. Lapen, J. Filiberto

Geoscience Faculty Research

Martian meteorites are the only direct samples from Mars, thus far. Currently, there are a total of 262 individual samples originating from at least 11 ejection events. Geochemical analyses, through techniques that are also used on terrestrial rocks, provide fundamental insights into the bulk composition, differentiation and evolution, mantle heterogeneity, and role of secondary processes, such as aqueous alteration and shock, on Mars. Martian meteorites display a wide range in mineralogy and chemistry, but are predominantly basaltic in composition. Over the past 6 years, the number of martian meteorites recovered has almost doubled allowing for studies that evaluate these meteorites …

Plio-Pleistocene Antarctic Ice-Ocean Interactions In The Ross Sea, Catherine Prunella

USF Tampa Graduate Theses and Dissertations

Warm, intermediate-depth Southern Ocean waters are implicated in recent Antarctic ice mass loss. Direct observations of Antarctic Ice Sheet (AIS) retreat are temporally limited, necessitating paleoceanographic records of ocean-ice interactions during past warm climate intervals. Deepsea and ice-proximal sediments record orbitally-paced glacial-interglacial fluctuations in AIS volume during the Plio-Pleistocene (last 5 million years; Ma), but the total contribution of the AIS and the role of ocean heat in these fluctuations remain unresolved. To address the response of Antarctica’s ice sheets to changing ocean temperatures during the Plio-Pleistocene, International Ocean Discovery Program (IODP) Expedition 374 recovered sediments from the Ross Sea …

Xenon Iron Oxides Predicted As Potential Xe Hosts In Earth’S Lower Mantle, Feng Peng, Xianqi Song, Chang Liu, Quan Li, Maosheng Miao, Changfeng Chen, Yanming Ma

Physics & Astronomy Faculty Research

An enduring geological mystery concerns the missing xenon problem, referring to the abnormally low concentration of xenon compared to other noble gases in Earth’s atmosphere. Identifying mantle minerals that can capture and stabilize xenon has been a great challenge in materials physics and xenon chemistry. Here, using an advanced crystal structure search algorithm in conjunction with first-principles calculations we find reactions of xenon with recently discovered iron peroxide FeO2, forming robust xenon-iron oxides Xe2FeO2 and XeFe3O6 with significant Xe-O bonding in a wide range of pressure-temperature conditions corresponding to vast regions in Earth’s lower mantle. Calculated mass density and sound …

Historical And Future Antarctic Precipitation Based On Cmip5 Models, Reanalysis Data And In Situ Measurements, Malcolm Tang Siong Yii

Student Works (2020-2029)

The study of precipitation in Antarctica is one of the most studied research topics today. The reliability and accuracy of climate models in simulating Antarctic precipitation, however, are still debatable. Measuring precipitation in Antarctica poses many distinctive challenges. This work attempts to establish a comprehensive study of precipitation in Antarctica. The first part of the study assesses a year-long measurements from five precipitation instruments with reanalysis datatsets and satellite data. The tipping bucket gauges (TBGs) were observed to be less sensitive compared to laser-based sensors (LBSs). Case studies of the daily precipitation and seasonal precipitation measurements showed VPF-730 to be …

Trends In Water Quality Of Cave Pools At Timpanogos Cave National Monument, July 2008–September 2018, Rebecca Weissinger, Andy Armstrong, Kirsten Bahr, Chris Groves

Crawford Hydrology Laboratory

No abstract provided.

Impacts Of Forest Management And Timber Harvest Practices On Karst Critical Zone Processes In Tongass National Forest, Alaska, Anna Gwendolyn Harris

Masters Theses & Specialist Projects

This study characterizes the throughfall, hydrogeochemistry, dissolution rates, and carbon sources of two proximate temperate rainforest cave systems within the Tongass National Forest in Southeast Alaska (Tongass). Study sites include: an old-growth forest, characterized by having never been logged (containing Walkabout Cave system); and a previously logged – within thirty years, second-growth forest (containing Zina Cave system). Precipitation data were recorded over a five-month period at 10-minute intervals, to understand the effects of throughfall between the altering old and second-growth canopies. At each major spring for the two cave systems, high-resolution data were collected from June 29 through November 21, …

Interpretations Of Lava Flow Properties From Radar Remote Sensing Data, Gavin Douglas Tolometti, Catherine Neish, Gordon R. Osinski, Scott S. Hughes, Shannon E. Kobs-Nawotniak

Earth Sciences Publications

The surface morphology and roughness of a lava flow provides insight on its lava properties and emplacement processes. This is essential information for understanding the eruption history of lava fields, and magmatic processes beneath the surface of Earth and other planetary bodies such as the Moon. The surface morphology is influenced by lava properties such as viscosity, temperature, composition, and rate of shear. In this work, we seek to understand how we can interpret the emplacement processes and lava properties of lava flows using remote sensing data. Craters of the Moon (COTM) National Monument and Preserve in Idaho hosts a …

Iron Speciation In Pm2.5 From Urban, Agriculture, And Mixed Environments In Colorado, Usa, Joseph R. Salazar, David J. Pfotenhauer, Frank Leresche, Fernando L. Rosario-Ortiz, Michael P. Hannigan, Sirine C. Fakra, Brian Majestic

Chemistry and Biochemistry: Faculty Scholarship

Atmospheric iron solubility varies depending on whether the particles are collected in rural or urban areas, with urban areas showing increased iron solubility. In this study, we investigate if the iron species present in different environments affects its ultimate solubility. Field data are presented from the Platte River Air Pollution and Photochemistry Experiment (PRAPPE), aimed at understanding the interactions between organic carbon and trace elements in atmospheric particulate matter (PM). 24-hr PM2.5 samples were collected during the summer and winter (2016–2017), at three different sites on the Eastern Colorado plains: an urban, agricultural, and a mixed site. Downtown Denver had …

Experimental And Thermodynamic Constraints On Mineral Equilibrium In Pantelleritic Magmas., Pierangelo Romano, Bruno Scaillet, John C. White, Joan Andujar, Ida Di Carlo, Silvio G. Rotolo

EKU Faculty and Staff Scholarship

Crystallization experiments on two pantellerites from Pantelleria, Italy, provide new evidence for the relation-ships between mineral phases in pantelleritic rocks as well as the influence of temperature and redox conditionson mineral assemblages. Experiments were performed at 1 kbar with temperature ranging between 750–900°C,andfluid saturation conditions with XH2O (=H2O/H2O+CO2) between 0 and 1. Redox conditions were fixed at, or slightly below, the FMQ buffer. Results show that at temperature of 900 °C pantelleritic magmas are well above the liquidus regardless their water content; we also observed a decrease in liquidus temperature (800°C) with increasingly reducing conditions. Mineral assemblages of the natural …

Molecular Tests Support The Viability Of Rare Earth Elements As Proxies For Fossil Biomolecule Preservation, Paul V. Ullmann, Kristyn K. Voegele, David E. Grandstaff, Richard D. Ash, Wenxia Zheng, Elena R. Schroeter, Mary H. Schweitzer, Kenneth J. Lacovara

School of Earth & Environment Departmental Research

The rare earth element (REE) composition of a fossil bone reflects its chemical alteration during diagenesis. Consequently, fossils presenting low REE concentrations and/or REE profiles indicative of simple diffusion, signifying minimal alteration, have been proposed as ideal candidates for paleomolecular investigation. We directly tested this prediction by conducting multiple biomolecular assays on a well-preserved fibula of the dinosaur Edmontosaurus from the Cretaceous Hell Creek Formation previously found to exhibit low REE concentrations and steeply-declining REE profiles. Gel electrophoresis identified the presence of organic material in this specimen, and subsequent immunofluorescence and enzyme-linked immunosorbant assays identified preservation of epitopes of the …

Geology, Geochemistry And Petrotectonic Setting Of Idanre Granite Complex, Southwestern Nigeria, Akinola Oluwatoyin Olagoke

Student Works (2020-2029)

During Neoproterozoic, Nigeria like many other Pan-African countries witnessed extensive magmatic activities which resulted in emplacement of granite popularly referred to as Older Granite in Nigeria. The study area is characterized by a large population of this rock type than any other part of Nigeria, so these rocks are investigated in this research. Idanre is underlain by migmatite-gneiss, charnockite and granite. Migmatite form the country rock and are low-lying, charnockite was surrounded by granite, while the granite forms large inselbergs. Three textural types of granite occur in the area, they are coarse-grained granite (undifferentiated) (OGu), porphyritic granite (OGp) and the …

Investigation Of The Interaction Of Gadolinium With Several Organic Ligands And Humic Acid By Ligand Competition Using 4-(2-Pyridylazo)-Resorcinol (Par), Spencer Steinberg, Vernon Hodge, Luis Becerra-Hernandez

Chemistry and Biochemistry Faculty Research

Gd3+ forms a strongly colored complex with 4-(2-pyridylazo)-resorcinol (PAR) in aqueous solutions. We characterized the Gd3+-PAR complex in order to use it as a probe of Gd3+ speciation in the presence of environmentally relevant ligands. The formation of the Gd3+-PAR complex was investigated from pH 5 to 8 in the presence of excess PAR. The absorbance of the Gd3+-PAR complex dramatically increased from pH 5 to 8 and application of the method of continuous variation indicates that the complex was primarily 1:2 Gd(PAR)2 at pH 8. Stability constants for Gd3+ with other ligands can be quantified by competitive displacement of …

Geochemical Characterization Of Base Metals In Stream Water And Sediments In The Caddo Lake Watershed, Cass, Harrison, And Marion Counties, Texas, Melinda S. Faulkner, Melanie L. Ertons, Joseph D. Watkins

Faculty Publications

The Caddo Lake watershed is located in northeastern Texas and encompasses much of Cass, Harrison, and Marion counties. The watershed is drained by major streams and tributaries flowing in an easterly direction over Eocene-aged rocks and sediments of the Wilcox and Claiborne groups, and empty into the western arm of Caddo Lake. Since 1995, Caddo Lake and some of its tributaries have been included on the State of Texas Clean Water Act 303(d) list by the Texas Commission on Environmental Quality (TCEQ) for impairment due to mercury content in edible tissue, depressed dissolved oxygen, base metal concentrations, and low pH …

Distribution, Geochronology, And Petrogenesis Of The Picture Gorge Basalt With Special Focus On Petrological Relationships To The Main Columbia River Basalt Group, Emily Bogdan Cahoon

Dissertations and Theses

The Columbia River Basalt Group (CRBG) is the youngest and volumetrically smallest continental flood basalt exposed across the Pacific Northwest, USA. Similar to other large igneous provinces, the majority of material erupted during the initial 1 million years of activity, these lavas are subdivided into four main-phase units. The Picture Gorge Basalt (PGB) is the only main-phase unit of the CRBG whose age is not precisely known and understanding of PGB petrogenesis is largely based on a limited number of samples when compared with other main-phase units. It is suggested that a time gap of over 0.5 myr existed between …