Geochemistry Commons^™

Distribution Of Particulate Organic Carbon – Fluxes And Inventories – In Growth-Faulted Coastal Wetlands, Samuel Joel Whitehead

Theses and Dissertations--Earth and Environmental Sciences

Coastal wetlands along the Northern Gulf of Mexico (NGOMx) are critically important but threatened environments which provide significant and diverse economic, social, and environmental value. These environments are essential components to the global carbon cycle, serving as one of the most efficient terrestrial carbon sinks. Since onset of the Industrial Revolution increasing rates of coastal wetland loss have been documented due to a variety of anthropogenic activities, neotectonic processes, subsidence, and rising sea-levels. This research utilized an array of methods and sedimentological analyses to test the hypothesis that growth-fault induced changes at Earth’s surface affects the delivery to, and storage …

U-Pb Apatite Chronometry Of Intrusions In An Accretionary Metamorphic Belt In Western Idaho, Usa, Colleen Grace Rankin

Graduate Theses/Dissertations

The Salmon River suture zone in west-central Idaho, USA records the tectonic processes where island arcs, similar to modern-day Japan, were accreted to the North American continent in the Jurassic and Cretaceous periods (160-90 million years ago). This suture zone contains metamorphic rocks that were buried deep within the crust at depths of 20 kilometers or more and have subsequently been brought to the surface. The exhuming processes responsible for the metamorphic rocks in the Salmon River suture zone remains unclear. Two competing hypotheses have been proposed to explain the transport of the rocks from the Salmon River suture zone …

Downstream Dispersal Of Fine Tailings, Chat And Metals In Channel Sediment Of Big River, Old Lead Belt, Southeast Missouri, Jennifer Pace Witt

Graduate Theses/Dissertations

In St. François County, Missouri, compromised above-ground tailings piles and containment ponds from historical mining activities in the Old Lead Belt released considerable amounts of dolomitic, Pb- and Zn-contaminated waste sediments to the Big River, contributing to significant downstream floodplain and channel sediment contamination. Previous studies have documented the effects of heavy metals on Big River biota and water quality, as well as benthic habitat disruption resulting from the influx of small sediments. Few have considered the effects and future contamination risk of the coarse waste sediments (2-16 mm in diameter), locally called “chat”, which retain high Pb and Zn …

Chemical And Thermal Influence On Intermediate Magma Storage Conditions: Volcán Ollagüe, Chile-Bolivia, Central Andes, Drew Allen Laviada-Garmon

Graduate Theses/Dissertations

Continental arc volcanoes are the single best portrayal of the evolution of recycled earth material stemming from subduction, one of the most important and foundational phenomena in global tectonics. Understanding the genesis of intermediate-composition magmas produced at arc volcanoes is a difficult process making them a focal point for investigation. Geochemical investigation of zircon and plagioclase mineral phases erupted from continental arcs can provide insight into magma process, generation, storage conditions, timescales and differentiation of sub-volcanic plumbing systems prior to eruption events. The Central Volcanic Zone is a prime example of continental arc volcanism through subduction, and is host to …

Determining Spatial Controls On Snow Isotopic Signature And Tracing The Snowmelt Pulse As It Moves Through Two Montane Catchments, Jenna K. Rolle

Graduate Student Theses, Dissertations, & Professional Papers

In this study, we investigate the spatial and temporal distribution of stable isotopes of oxygen and hydrogen in water across two mountainous catchments in west-central Montana to trace the input of snow to local soil, bedrock aquifers, and streams. Snowpack and snowmelt samples were collected throughout the winter season at ten sites selected to encompass a range of elevation, aspect, slope angle and hillslope position. Soil and bedrock wells at five of the ten sites were sampled after the initial snowmelt pulse and stream samples were collected weekly at the outlets of both catchments to trace the timing and partitioning …

Stable Isotope Analysis Of A Platecarpus Tympaniticus (Squamata, Mosasauridae) With Actinocamax Sternbergi (Mollsuca, Belemnoidea) Reveals Possible Endothermic Thermoregulation, Mitchell Lukens

Master's Theses or Doctor of Nursing Practice

Mosasaurs, ancient marine reptiles, dominated the late Cretaceous oceans. However, their ecological success is a contentious topic. Were they ectothermic, like their modern relatives the varanid lizards? Or endothermic like extant marine mammals? Stable isotopes can reveal temperature and physiological variances within skeletons, but do not differentiate between body temperature and ambient environmental temperature. A rare mosasaur specimen from the Smoky Hill Chalk of a partial, articulated Platecarpus tympaniticus with stomach contents of belemnites provides a possible direct temperature contrast between predator and prey. The belemnites, related to modern coleoids, are identified as Actinocamax sternbergi. These animals possessed body …

Using Geochemical Composition To Determine Paleo Environmental Conditions And Source Inputs In Paleozoic Rocks Within The Central Kansas Uplift Usa, Christiana Fumnanya Eziashi

Master's Theses or Doctor of Nursing Practice

Paleoenvironmental conditions, sediment characteristics and lateral continuity using chemostratigraphy are not well established for stratigraphic units associated with some small fields within the Central Kansas Uplift (CKU). Samples of drill cuttings recovered from six wells (Hottman #1, and Hottman-Furthmeyer#1, Yocemento #1, Mong Benno #2, Rhian #3 and Worcester #1) at 10 ft intervals between 3150 ft and 3900 ft below ground level, were processed and analyzed using X-ray fluorescence (XRF) and X-Ray diffraction (XRD). The XRF technique was used to determine elemental compositions, and XRD was used to determine mineral content. The composition of the rock cuttings was used to …

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth

Williams Honors College, Honors Research Projects

It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H₂O₂ was the experimental factor to further test FeRB tolerance. H₂O₂ is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H₂O₂ concentrations were fed …

Defining The Endmember System Of Us Soils And Quantifying Relationships, And A Hyperspectral Approach To The Alteration Strength Index, Rachel Rulison

Dissertations, Master's Theses and Master's Reports

Soils form a complex part of the environment, providing important functions in systems such as food production, groundwater movement, and ecosystem health. There have been numerous studies on soil geochemistry and the origin of elements within soils, but few studies into quantifying the relationships between elements and geographical data on a national scale. Using geochemical data obtained by the USGS, the surficial soils of the US were defined by a 13-endmember system using Polytopic Vector Analysis and mapped in GIS. Correlation matrices provided Pearson’s correlation coefficients for elements in the Top 5 cm soil profile, the A horizon, and the …

Mining-Contaminated Sediment And Metal Storage In Channel Deposits In Turkey Creek, Tri-State Mining District, Missouri And Kansas, Max Quinn Hillermann

Graduate Theses/Dissertations

The Joplin subdistrict, within the Tri-State Mining District (TSMD), was a major producer of lead (Pb) and zinc (Zn) ore between the 1880s to 1920s. Metalliferous mining wastes are still stored in the channel deposits of local streams raising environmental and health concerns. This study quantifies the volume, sediment size, and metal concentrations in channel bed, bar, bench, and chute deposits to quantify the spatial variability of contaminated sediment storage in Turkey Creek (119 km²). Sample reaches (n=14) contained metal concentrations elevated above the Tri-State Mining District specific probable effects concentration at every site with mean concentrations in …

Aucanquilcha Volcanic Cluster Magma Evolution And Magma Plumbing System Architecture During The Gordo Stage (6-4 Ma), Kasey Lynn Buckley

Graduate Theses/Dissertations

Aucanquilcha Volcanic Cluster (AVC) is an 11 m.y. volcanic system in the central Andes that is evolving over four distinct stages of activity. Stages include the Aloncha (11-8 Ma), Gordo (6-4 Ma), Polán (4-2 Ma), and Aucanquilcha (Ma) stages. The AVC evolved from a series of magmatic underpinnings during the Aloncha Stage to a larger zone of melting, assimilation, storage, and homogenization (MASH) by the Polán Stage. The transition from smaller underpinnings to MASH zones began during the Gordo Stage. At ~5-2 Ma the AVC reached thermal maturity before beginning its volcanic death during the Aucanquilcha Stage. This study focuses …

Disequilibrium Melting Of The Continental Crust During Emplacement Of The Mt. Princeton Batholith, Central Colorado Volcanic Field, Loren A. Bohannon

Graduate Theses/Dissertations

Assimilation and crystallization are difficult to constrain at magmatic boundaries, including the interactions of magma with the surrounding country rock. The assumption of the relationship between a magma and what it is intruding upon is relegated to homogenous bodies or epizonal plutons. Realistically, wall rock influences chemical heterogeneity and isotopic variance at the outcrop scale and changes depending on distance from the magma-wall rock interface. Here, we present a case study of the 35 Ma Mt. Princeton Batholith and the host Precambrian rocks of the Central Colorado Volcanic Field. We assess chemical heterogeneity by whole rock and mineral trace element …

Evaluating Holocene Precipitation Variability In The Baltic Region Using Oxygen Isotopes Of Lacustrine Carbonate From Estonia, Maxwell Gordon Boes

Graduate Research Theses & Dissertations

A high-resolution Holocene record of groundwater isotopic composition from eastern Europe enhances the current understanding of ocean atmosphere interactions and moisture transport dynamics. In the modern system, it has been established that the amount of regional winter precipitation is driven by the strength and direction of the sea level atmospheric pressure gradient over the Atlantic Ocean. This is defined by the North Atlantic Oscillation (NAO) index, that shows a positive correlation with precipitation amount during the cold season. This study aims to discover the link between atmospheric dynamics and the ratio of warm season to cold season precipitation through the …

Chemical Characterization Of Clastic Cave Sediments And Insights Into Particle Transport And Storage In Karst Aquifers, Jill L. Riddell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Chemical characterization of clastic cave sediments and insights into particle transport and storage in karst aquifers

Jill L. Riddell

Cave sediments can be divided into two groups: precipitates and clastics. Precipitates are speleothems, or lithologic or mineral features that are chemically precipitated in the cave environment. Clastic cave sediments are frequently described by depositional facies, sorting, and particle size (Bosch and White, 2004). Robust analytical chemical analyses of these sediments to quantify their physical and chemical components is rarely performed although some chemical characterization of mineralogy and paleomagnetism has become prevalent in recent years (Chess et al., 2010; Sasowsky …

The Effects Of Channel Incision And Land Use On Surface-Water/Groundwater Interactions In The Teanaway River Basin, Washington, Usa, Joseph Petralia

All Master's Theses

The Teanaway River basin, a major tributary to the Yakima River, is host to several restoration projects with the intention of returning the river channel to a more natural state and improving riparian habitat. These projects may also increase aquifer storage and potentially increase summertime streamflows. This study of the Teanaway Valley Family Farm, an 88-hectare parcel on the main-stem Teanaway River that was recently purchased by Washington Department of Fish and Wildlife, provides hydrogeologic data that will inform these restoration projects. Following the purchase of this land, ten wells were installed within and slightly above the floodplain in order …

Impact Of Prairie Restoration On Geochemistry And Microbial Communities In Groundwater, Kayla Koenig

Graduate Research Theses & Dissertations

Prairie restoration is important for reversing the loss of biodiversity and repairing ecosystem functions humanity is dependent on diverse ecosystems. This study looks at the impact of the beginning phases of prairie restoration on groundwater geochemistry and microbial communities the relationship between them. This research project studied the geochemistry and microbial communities in five wells before, during, and after the beginning phases of the first year of a prairie restoration on the Northern Illinois University campus. Water samples were collected bimonthly for a year and analyzed on an Ion Chromatograph. Microbial samples were collected monthly and underwent DNA extraction, amplification, …

Structural And Petrologic Insights Into The Emplacement Of Effusive Silicic Lavas: Inyo Domes, California, Shelby L. Isom

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Long Valley volcanic region, eastern California, USA is most famous for the caldera-forming eruption which produced the Bishop Tuff ~760,000 years ago. Over the last 3,000 years volcanism has been focused in the western margin of the region through punctuated eruptions of silicic lavas and domes. Three simultaneous effusive silicic eruptions, ~600 years ago, generated three lava domes: Obsidian Dome; Glass Creek Dome; and Deadman Dome which erupted onto vastly different topographies. These domes are exceptionally unique as they erupted variable amounts of two textural and chemical endmember lavas (crystal-rich and crystal-poor) that intimately mixed. The overarching goal of …

Stratigraphic Analysis Of The Capps Limestone In The North Norton Oil Field In Runnels County, Texas, William Thompson

Electronic Theses and Dissertations

The Desmoinesian (Middle Pennsylvanian) Capps Limestone Member of the Mineral Wells Formation is a carbonate reservoir located in North Central Texas. It consists of interbedded limestone, sandstone, and shale units. Much of the Capps Limestone exists in the subsurface of Brown, Coleman, Runnels, Coke, Nolan, and Taylor counties, however, the Capps Limestone outcrops on the surface in Brown, Eastland, and Palo Pinto counties.

The cored interval from Runnels County was deposited in a marginal marine environment during the Middle Pennsylvanian Period. Although the Capps Limestone was first described in the 1890s, there is still much to be discovered about its …

Identifying Biogeochemical Factors Responsible For The Cyclical Precipitation Of Sphalerite And Galena In Low Temperature Mississippi Valley Type Ore Deposits, Daniel John Makowsky

Theses and Dissertations

Mississippi Valley Type (MVT) lead and zinc deposits provide a significant source of sedimentary galena and sphalerite. However, geochemical characteristics and genesis including the source and production of hydrogen sulfide required for galena and sphalerite ore formation and the reasoning for quick, episodic mineralization is not fully understood. By simulating regional MVT brines, the input and effect of biological by-products during the development of these ores as well as the cause of cyclicity within MVT deposits have been observed. Experiments using compositions from MVT fluid inclusions were conducted over two-week periods. Variables during the experiments included temperature, CO2, hydrogen sulfide …

Using Sedimentary Mercury Geochemistry To Evaluate The Niagara-Salina Transition, Silurian Michigan Basin, Usa, Sara Hayes

Masters Theses

The Niagara-Salina boundary in the Michigan Basin is marked by an abrupt transition from carbonates to evaporites. Though the cause is uncertain, previous work suggests the onset of Salina evaporites was driven by basin restriction, but the presence of several global carbon isotope excursions (CIE) suggest a global driver. This study builds on this discussion using two relatively new geochemical proxies - elemental mercury concentrations [Hg] and Hg isotopes.

Mercury concentrations [Hg] were measured in 88 samples from the State Kalkaska #2-15 core from 6604.03 ft to 6797.42 ft. [Hg] ranges from 0.11 to 0.62 mg/kg and [Hg]/TOC from 0.038 …

Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton

Mechanical Engineering Undergraduate Honors Theses

River channels have been observed near the Huygens probe landing site on the surface of Titan, along with evidence of rounded water ice boulders transported through fluid flow. Evidence near the landing site suggests active flow of liquid methane, which has motivated the study of the effects of sediment load and channel sizes on Titan’s fluvial features. A numerical model is used to determine the viscosity, flow velocity, and critical boulder transport diameter based on channel size, slope, and a range of sediment concentrations. This model achieves two ends: first, observed boulder diameters are used to determine the ideal channel …

Geochemical Investigation Of Monogenetic Volcanoes From The Pribilof Islands, Bering Sea, Alaska, Clayton L. Reinier

Graduate Theses/Dissertations

Small-volume basaltic magmas found at continental intraplate environments have not been as extensively studied compared to their polygenetic counterparts. Specifically, regions such as the Bering Sea basalt province, described as a diffuse igneous province, have commonly been overlooked. Assumptions that these systems are invoked by simple, single batches of magma has subsequently left a gap in understanding the processes responsible for primary magma generation away from plate boundaries with little tectonic influence. The following studies that constitute this thesis focus on an in-depth geochemical investigation at the crystal and sub-crystal scale to evaluate lithospheric mantle heterogeneities, processes that govern primary …

Low Impact Sampling Of Speleothems – Reconciling Scientific Study With Cave Conservation, Claire L.V. Macgregor, John C. Hellstrom, Jon D. Woodhead, Russell N. Drysdale, Rolan S. Eberhard

International Journal of Speleology

Speleothems are increasingly valued as important paleoclimate archives and yet the removal of samples from caves can come at a cost to natural heritage, impacting delicate environments with limited mechanisms for repair. Conservation of cave environments is a key responsibility for scientists and, with this in mind, we are working to develop and implement techniques that allow us to extract valuable scientific data, with minimal impact. In this study, we demonstrate the utility of low-impact reconnaissance dating surveys on caves in southern Tasmania and southwest Western Australia as a precursor to the removal of stalagmites for paleoclimate reconstruction. Small flakes …

Revisiting The Cretaceous-Paleogene Boundary In Western Kentucky, Usa, Jarred Asselta

Scholars Week

This study revisits a Cretaceous-Paleogene (K-Pg) sedimentary section in western Kentucky to determine the nature of this boundary and the depositional environments. Although previous pollen work identified the boundary over four decades ago, to our knowledge no work has been carried out at this important K-Pg boundary site. A combination of stratigraphy and sedimentology were used to characterize the section in detail. Bulk and oriented samples were collected for grain-size, geochemical, and petrographic analysis. We relocated the site and measured 1.5m of section that includes the K-Pg boundary. Four distinct units were identified and from base to top of section …

Hydrological Feedbacks On Peatland Ch4 Emission Under Warming And Elevated Co2: A Modeling Study, Fenghui Yuan, Yihui Wang, Daniel M. Ricciuto, Xiaoying Shi, Fengming Yuan, Thomas Brehme, Scott Bridgham, Jason Keller, Jeffrey M. Warren, Natalie A. Griffiths, Stephen D. Sebestyen, Paul J. Hanson, Peter E. Thornton, Xiaofeng Xu

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatland carbon cycling is critical for the land–atmosphere exchange of greenhouse gases, particularly under changing environments. Warming and elevated atmospheric carbon dioxide (eCO₂) concentrations directly enhance peatland methane (CH₄) emission, and indirectly affect CH₄ processes by altering hydrological conditions. An ecosystem model ELM-SPRUCE, the land model of the E3SM model, was used to understand the hydrological feedback mechanisms on CH₄ emission in a temperate peatland under a warming gradient and eCO₂ treatments. We found that the water table level was a critical regulator of hydrological feedbacks that affect peatland CH₄ dynamics; the …

Timescales Of Magma Transport In The Columbia River Flood Basalts, Determined By Paleomagnetic Data, Joseph Biasi, Leif Karlstrom

Other Staff Materials

Flood basalts represent major events in Earth History, in part because they are linked to large climate perturbations and mass extinctions. However, the durations of individual flood basalt eruptions, which directly impact potential environmental crises, are poorly constrained. Here we use a combination of paleomagnetic data and thermal modeling to create a magnetic geothermometer (MGT) that can constrain the active transport lifetime of magmatic conduits and intrusions. We apply the MGT technique to eight feeder dike segments of the Columbia River basalts (CRB), demonstrating that some dike segments were actively heating host rocks for less than one month, while other …

Diffusional Fractionation Of Helium Isotopes In Silicate Melts, Haiyang Luo, Bijaya Karki, Dipta B. Ghosh, Huiming Bao

Faculty Publications

Estimating Helium (He) concentration and isotope composition of the mantle requires quantifying He loss during magma degassing. The knowledge of diffusional He isotope fractionation in silicate melts may be essential to constrain the He loss. Isotopic mass dependence of He diffusion can be empirically expressed as D3He/D4He = (4/3)^β, where D is the diffusivity of a He isotope. However, no studies have reported any β values for He in silicate melts due to technical challenges in both experiments and computations. Here, molecular dynamics simulations based on deep neural network potentials trained by ab initio data …

Continuous Color Model As A Tool To Improve Speleothem Age Model Development, Celia Campa-Bousoño, Ángel García-Pérez, Ana Moreno, Miguel Iglesias, Hai Cheng, R Lawrence Edwards, Heather Stoll

International Journal of Speleology

Because they can archive a variety of geochemical proxies and be precisely and accurately dated with the U-Th decay series chronometer, stalagmites are widely used for paleoclimate reconstructions. However, limitations in the use of this chronometer arise because U-Th dating is analytically time consuming, expensive, and requires a relatively large sample size. These limitations restrict the number of absolute dates usually obtained, which can result in significant uncertainties in the age model and inhibit the ability to archive high resolution records of environmental variability, particularly in those stalagmites where there are variations in growth rate not constrained by U-Th dates. …

Timescales And Dynamics Of Rhyolitic Melt Generation In Upper Crustal Magmatic Reservoirs: Insights From New Geochronologic And Petrologic Data On The Valle Mosso Pluton And Sesia Caldera, Sesia Magmatic System, Italy, Lorenzo Tavazzani

Earth Sciences Theses and Dissertations

This work may have a narrow geographic focus, namely a handful of steep and densely forested valleys of the Southern Italian Alps, but its scientific goals are certainly wide. Through a combined analyses of the spatial distribution, geochemical characteristics and temporal duration of the Permian silicic magmatism in the renown Ivrea crustal section (Sesia Magmatic System), this dissertation addresses fundamental questions regarding the physical mechanisms of rhyolitic magma storage, mobilization and eruption.

A brief introduction serves to define the broader context of the scientific questions addressed in the three main chapters of this dissertation. Through Chapters 2 to 4 we …

Geochemistry Of Phosphatic Nodules As A Tool For Understanding Depositional And Taphonomical Settings In A Palaeolithic Cave Site (San Teodoro, Sicily), Gerlando Vita, Vittorio Garilli, Mirko Andrea Vizzini, Renato Giarrusso, Angelo Mulone, Massimiliana Pinto Vraca, Valeria La Parola, Pierluigi Rosina, Laura Bonfiglio, Luca Sineo

International Journal of Speleology

Interpreting depositional settings of cave sites is generally problematic, especially in absence of paleontological/archaeological evidence. This is the case of some deposits at San Teodoro Cave (Sicily), a key site for the Mediterranean Palaeolithic. In a stratigraphic level interrupted by a carbonatic concretion, phosphatic nodules are present only in the part enclosed between the concretion and the cave wall. The discovery of these nodules combined with the punctual lack of fossils had initially suggested an erosion phenomenon and subsequent formation of nodules at a vadose level. Here we show the usefulness of an integrated, geochemical-paleoecological approach in defining stratigraphy and …