Geochemistry Commons^™

The Legacy Of Mining In Southwest Missouri: Past And Present Conditions Of The Tri-State Mining District, Anastasia M C Mcclanahan

Graduate Theses/Dissertations

The historic Tri-State Mining District (TSMD) of southwestern Missouri, southeastern Kansas, and northeastern Oklahoma has a history of lead and zinc mining that extended over a hundred years. During the district’s peak production period, the TSMD was one of the world’s largest producers of lead and zinc. The mining activities in the TSMD produced economic growth that supported the local communities and were essential to the victory of the Allied Forces during World War I and World War II. Beginning in the 1920s, the mining activities in the district slowly began to cease due to depletion of metal ores and …

Geochemical Variability & Implications For Magma Transport At 14°N On The Mid-Atlantic Ridge, Emma Elizabeth Mccully

Boise State University Theses and Dissertations

Observations of seafloor bathymetry and gravity surveys indicate that magma focuses in the center of slow spreading Mid-Ocean Ridge (MOR) segments, however; it is not well constrained how magma is generated, stored, and transported to the segment ends. There are two end-member models for magma transport: 1) a focused magma model wherein the magma upwells beneath the entire ridge axis, is focused and pools beneath the center of the segment, and is then transported towards the segment ends via lateral diking in the shallow crust and 2) a distributed magma model wherein magma vertically upwells and is erupted on the …

Connections Between Hydrothermal System Geochemistry And Microbiology: Traversing Tectonic Boundaries In The South-Central Peruvian Andes, Heather Upin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geochemistry and microbiology are inherently tied in the natural world. The study of geomicrobiology has historically taken place in extreme systems, like hot springs of Yellowstone National Park and deep-sea hydrothermal vents, because the organisms that exist there have deep lineages on the tree of life and provide insight into early life on Earth. These microbes use chemical energy from nutrients available in their environment rather than relying on photosynthesis, energy obtained from the sun, to support their metabolism. The goal of this study is to improve our understanding of geological controls (for example the tectonic setting) on hot spring …

Structural Characterization Of Organic Matter In Oil Shales Using Multiple Nuclear Magnetic Resonance Spectroscopic Techniques, Wenying Chu

Chemistry & Biochemistry Theses & Dissertations

Oil shale is a promising source of hydrocarbon fuel that is distributed throughout the world. The petroleum generating potential of oil shale is related to the molecular structure of the organic matter in source rock. The major fraction of organic matter of oil shale is termed kerogen, and due to its insolubility in organic solvents, ¹³C solid-state nuclear magnetic resonance (NMR) spectroscopy is one of the best ways to directly measure the insoluble organic matter without changing its chemical structures. This dissertation investigated oil shale samples using advanced solid-state ¹³C NMR spectroscopy techniques and high resolution magic angle …

Detrital Zircon Petrochronology For Sedimentary Provenance Analysis: Source To Sink Of The Mississippi/Missouri River Drainage Basin, Sage Denali Muttel

Graduate Theses/Dissertations

Detrital petrochronology can provide a detailed look into sedimentary provenance through integrated mineral radioisotopic ages with corresponding mineral chemistry. By combining U-Pb ages and Th/U values of detrital zircon from 13 samples collected from Quaternary sand deposits in the Upper Missouri, Yellowstone, Bighorn, Platte, Kansas, Arkansas, Mississippi, Red and Brazos Rivers, an interpretation of detailed signatures that record evidence of the evolution of the Mississippi/Missouri River drainage and the tectonic events that shaped it were observed. Low Th/U values in zircon correlate temporally to convergent magmatism, whereas, higher and more variable Th/U zircon are coeval with known extensional tectonism. Using …

Triple Oxygen Isotope Composition Of Carbonates, Jordan A.G. Wostbrock

Earth and Planetary Sciences ETDs

This dissertation presents a method of analyzing the triple oxygen isotope compositions of carbonates, presents an empirical calibration of the carbonate-water equilibrium fractionation line, presents a triple oxygen isotope equipped fluid-rock mixing model for carbonates to see-through diagenesis, and applies all these findings to ancient carbonate samples. Using modern carbonates and associate water, the following equations are calculated to describe equilibrium triple oxygen isotope fractionation of carbonates:

1000lnalpha¹⁸O_cc-wt=2.84x10⁶/T²-2.96 1),

Theta_cc-wt=-1.39/T+0.5305 2).

Using these fractionation equations provides an extremely useful tool to determine whether a carbonate sample is altered or preserves …

Phosphorus Variability In The Area Of Influence Of The Mid-Barataria Sediment Diversion, Peter Mates

LSU Master's Theses

Man-made levees along the lower Mississippi River prevent delivery of sediment from building and maintaining Louisiana’s coastal wetlands. The Mid-Barataria sediment diversions is designed to reintroduce Mississippi River water, sediment, and nutrients into the sediment-starved Barataria Basin. Phosphorus (P) is an important macronutrient for regulating primary production in coastal marine ecosystems. Wetlands can serve as a sink or source for phosphorus to the overlying water column through various retention and release processes, dependent on concentration. Louisiana coastal systems can be phosphorus limited due to much higher concentrations of bioavailable Nitrogen in river water. The high soluble molar N:P ( >50:1) …

A Bayesian Framework To Unravel Food, Groundwater, And Climate Linkages: A Case Study From Louisiana, Nitin K. Singh, Ruchi Bhattacharya, David M. Borrok

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Advancing our understanding of the connections among groundwater, food, and climate is critical to meet global food demands while optimizing water resources usage. However, our understanding of the linkages among groundwater, food, and climate is still limited. Here, we offer a Bayesian framework to simulate crop yield at a regional scale and quantify its relationships and associated uncertainty with climate, groundwater, agricultural, and energy-related variables. We implemented the framework in the rice-producing regions of Louisiana from 1960-2015. To build a parsimonious model, we used a probability-based variable selection approach to detect the key drivers of rice yield. Rice yield increased, …

Characterizing Peridotite Xenoliths From Southern Vietnam: Insight Into The Underlying Lithospheric Mantle, Kirby Hobbs

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Extrusion tectonics has been invoked to explain the extensive basaltic magmatism that has erupted over Indochina within the last 17 Ma. The basalts display two-stage eruptive cycles consisting of tholeiites followed by alkaline basalts. Lithospheric mantle xenoliths recently sampled from the alkaline basalts of two volcanic centers, Pleiku and Xuan Loc, primarily consist of fertile spinel lherzolites, and Xuan Loc also contains refractory spinel harzburgites. We measured major elements in xenolith mineral separates, trace elements in clinopyroxenes and orthopyroxenes, and Pb-Sr-Nd isotopic compositions in clinopyroxenes to determine the origin and history of the subcontinental lithospheric mantle (SCLM) beneath Vietnam. Most …

Effects Of Terrestrial Weathering On Rare Earth Element Concentrations And Sulfur Isotopic Signatures Of Carbonaceous And Ordinary Chondrites, Ruby Virginia Patterson

Graduate Theses and Dissertations

Understanding the effects of weathering of chondrites is essential to gaining accurate and useful information about the formation of our solar system, as well as a more detailed account of the mobilization of chondritic compounds when they encounter terrestrial conditions. Elemental concentrations and stable isotope analyses of chondrites, considered to be the most primordial material in the solar system, are two tools which help unlock the weathering patterns of these specimens when they enter the earth system. However, it is not currently known exactly how time spent in the field alters rare earth element (REE) concentration or δ34S signatures within …

Investigating The Isotope Signatures Of Dissolved Iron In The Southern Atlantic Ocean, Brent A. Summers

USF Tampa Graduate Theses and Dissertations

Iron (Fe), used as a cofactor in nitrogen fixation and photosynthesis by oceanic microorganisms, has extremely low dissolved concentrations in the surface ocean, leading to widespread limitation of phytoplankton growth. Dissolved Fe isotope ratios (δ56Fe) have been shown to be useful in helping to quantify the sources and cycling of Fe in the oceans if Fe source signatures and fractionation processes are well understood. Here, this thesis presents data from GEOTRACES section GA10W, and investigate the isotopic signature of sediment-derived dissolved Fe from the South Atlantic margins. My results show that there are both shallow (δ56Fe of -0.2‰) and deep …

Anthropogenically Expedited Transit Reduces Organic Carbon Loss In The Lower Mississippi River: Dataset, Zhixiong Shen, Brad E. Rosenheim, Torbjörn E. Törnqvist, Andreas Lang

College of Science Data Sets

This dataset presents data to investigate the change of organic carbon carried by the Lower Mississippi River (LMR) related to river engineering. The dataset includes (1) OSL data, (2) 14C data; (3) the channel centerline of the LMR in the 1970s, (4) the channel centerline of the LMR in 2019, and (5) the migration rates of the LMR between the 1970s and 2019.

An Investigation And Comparison Of Stable Isotopes In Meteoric Waters And Groundwaters From Southern Washington, Emily E. Smoot

University Honors Theses

A main source of freshwater in the Pacific Northwest is the Columbia River Basalt Group aquifer system. The semi-arid region of eastern Washington has undergone heavy groundwater depletion in recent decades due to increasing population and expanding agricultural use. Aggressive mining has resulted in drawdowns of up to 30 meters. By using stable isotopes oxygen-eighteen (¹⁸O) and deuterium (D), this study confines the timing of groundwater precipitation and proposes an explanation for why drawdowns are so significant. The isotopic composition of meteoric water is compared to groundwaters from southeast Washington. The two populations are statistically different (p < 0.001, alpha = 0.05). The isotopic composition of groundwaters from the deepest wells (< -150 m msl) are isotopically lighter than meteoric waters and not achievable by recharge under the current climate. These deep groundwaters are interpreted to have precipitated during the Last Glacial Maximum in the late Pleistocene and finished precipitating roughly 5 ka. Thus, replenishment of the aquifer cannot be expected to keep pace with extraction. Additionally, this research examines the elevation response in the stable isotope signature of meteoric water along the 47° N latitude by computing three lapse rates for ^{18 …}

Seasonal Transport Of Dissolved Inorganic Carbon And Total Alkalinity Across The Louisiana Shelf, Michelle M. Anderson

LSU Master's Theses

Rivers and wetlands are a major source of terrestrial derived carbon for coastal ocean margins. Unfortunately, Louisiana’s wetlands are threatened by ongoing high rates of erosion, deterioration, and unprecedented rates of river water discharge that changes seasonally, leading to a net loss of terrestrial carbon into the northern Gulf of Mexico (nGOM). There exists a current lack of understanding about the distribution of dissolved inorganic carbon (DIC) and total alkalinity (TAlk) within the shallowest regions of the Louisiana shelf. Even less is known about how the transport of DIC alters seasonally with changes in river outflow and shelf currents. Quantifying …

Investigating Geochemical Processes Of Fluid-Rock Interactions On Materials Related To Energy And Environment, Zelong Zhang

LSU Doctoral Dissertations

Understanding the potential processes of radionuclides released from nuclear waste forms is essential to the safe disposal and containment of nuclear waste. Iodoapatite, a potential waste form for radioiodine, was chosen as a model system to examine the impact by common aqueous anions on iodine release processes. Four semi-dynamic leaching tests were performed using 0.1 mol/L NaCl, Na₂CO₃, Na₃PO₄, and Na₂SO₄ solutions respectively under 90 °C, 1 bar, fixed S/V ratio 5/m (sample surface area to solution volume), and with 24-hour replacement of the leaching solutions. Solution analysis and …

Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson

Electronic Theses and Dissertations

Sediment gravity flows into deep-water environments are important stratigraphic traps in lithologically diverse reservoirs generating multiple plays for hydrocarbon exploration. These highly heterogeneous deposits can be studied by utilizing chemostratigraphy and higher-order sequence stratigraphy; being an accurate method for reservoir characterization. Studying these gravity flows along a carbonate platform’s slope can further expand an understanding of the stratigraphy that is filling adjacent basins. The application of elemental analyses can support in identifying mineralogy that impact reservoir quality, especially when conventional testing cannot be applied.

This study utilizes five cores containing the Wolfcamp Formation from the southeastern slope of the Central …

A Geochemical Perspective On The Hydrocarbon Compositional Variation Within East Malay Basin: Implication For Oil Exploration, Mohd Sharef Nurfadhila

Student Works (2020-2029)

Malay Basin is a prospective basin which perceived to be matured basin in terms of hydrocarbon generating potential. Many significant oil discoveries made since 1970’s includes Seligi, Pulai, Tapis and Bekok oil fields. These fields have been producing until now. Despite its matured stage, there are still more oil discoveries in various parts of Malay Basin until now. Oil discoveries include light and high density oils with various challenges in oil development project. This dissertation focuses on oil fields in East Malay Basin particularly Lerek, Chermingat, Lawang and Serudon oil fields. The objectives of this research are to study the …

Integrating Detailed Petrography, Geochemistry, And Mineralogy To Elucidate Extensive Early Diagenesis In The Eocene Carbonates Of Qatar, Brooks H. Ryan

Dissertations

Eocene carbonates comprising the Umm er Radhuma (UER), Rus, and Dammam Formations, cover 80% of the surface and extend >300 m into the subsurface of Qatar. These rocks record marine sedimentation in shallow sub-tidal to restricted settings. Despite undergoing only shallow burial (<1000 m), extensive diagenetic alteration has occurred. Given that little work on this topic has been published previously, the objectives of this work are to document diagenesis in the Eocene, and to integrate petrography, mineralogy, and geochemistry to delineate the timing and environments of diagenesis of these Eocene carbonates. Detailed petrographic data show that dolomitization occurred early in the UER, before the formation of diagenetic chert, palygorskite, pyrite, calcite, and gypsum cements. Bulk dolomite δ¹⁸O values, coupled with clumped isotope-derived (Δ47) temperatures and dolomitizing fluid δ¹⁸O values, suggest dolomitization took place in near-normal marine fluids, perhaps during shallow burial. These data challenge the current paradigm of large-scale, top-down hypersaline reflux dolomitization in the UER. Associated depth trends of increasing crystal size and with increasing stoichiometry and cation ordering …

Space And Depth-Resolved Naturally Occurring Toxic Groundwater Species In Bangladesh And Rwanda: Origination And Risk Analysis, Kenneth Hamilton

Civil and Environmental Engineering Theses and Dissertations

Access to safe potable water is a necessity for all. Groundwater is a commonly relied upon drinking water source for many areas around the world. This is especially true for communities in high density, rural settings. Such is the case for populations near Cox’s Bazaar, Bangladesh, and in the Bugesera region of Rwanda. Sediment and groundwater contamination, through toxic dissolved species, represents a significant public health risk to exposed populations. Tropical soils, such as the soil profiles in Bangladesh and Rwanda, often contain higher concentrations of heavy metals (Rieuwerts, 2007). Additionally, nitrate from fertilizers, are widely used on the soils …

Chemistry Of Nanoscale Solids And Organic Matter In Sustainable Water Management Systems, Xuanhao Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

To alleviate global water scarcity and improve public health, engineered water treatment and management systems have been developed for purifying contaminated water and desalinating brackish or ocean water. These engineered systems provide substantial amounts of potable water and lessen environmental concerns about the release of contaminated water. Wastewater treatment plants (WWTPs), water desalination plants (WDPs), and managed aquifer recharge systems (MARs) are three representative sustainable water management (SWM) systems. But the operation of all three poses two fundamental questions: (1) What is the fate of nanoscale solids (e.g., engineered nanomaterials, naturally occurring nanoparticles) in SWM systems and how will their …