Geochemistry Commons^™

Evidence Of Variable Climate And Resources During The Late Pleistocene And Holocene At Gona, Ethiopia, Marie White

Steeplechase: An ORCA Student Journal

The African Humid Period (AHP) spanned a period of approximately 15 to 5 thousand years ago (ka) and resulted in Northern and Eastern Africa being wetter than today. This climate change event impacted flora, fauna, and humans to an unknown extent. Much of the work on the AHP across Eastern Africa utilizes lacustrine and marine proxies rather than river-based (fluvial). Gona, located in the Afar region of Ethiopia, is known for its extensive archaeological and fossil records in fluvial deposits. However, the paleoenvironment of the AHP at Gona has not been investigated. This study uses stratigraphy, geochronology, and paleopedology to …

Chemostratigraphic Correlations Across The First Major Trilobite Extinction And Faunal Turnovers Between Laurentia And South China, Jih-Pai Lin, Frederick A. Sunberg, Ganqing Jiang, Isabel P. Montanez, Thomas Wotte

Geoscience Faculty Research

During Cambrian Stage 4 (~514 Ma) the oceans were widely populated with endemic trilobites and three major faunas can be distinguished: olenellids, redlichiids, and paradoxidids. The lower–middle Cambrian boundary in Laurentia was based on the first major trilobite extinction event that is known as the Olenellid Biomere boundary. However, international correlation across this boundary (the Cambrian Series 2–Series 3 boundary) has been a challenge since the formal proposal of a four-series subdivision of the Cambrian System in 2005. Recently, the base of the international Cambrian Series 3 and of Stage 5 has been named as the base of the Miaolingian …

The Potential Of Radium-224 As A Tracer Of Timescales Of Gulf Of Mexico Crude Oil Exposure To The Marine Environment, Matthew T. Kurpiel

Electronic Theses and Dissertations

Petroleum pollution in the marine environment can be deleterious to coastal and marine ecosystems and can have sustained effects for years. While oil slicks on the surface of the ocean are tracked with relative ease using satellite-based technology, deep sea, neutrally-buoyant hydrocarbon plumes remain exceedingly difficult to track. We provide evidence for the utility of Ra-224 as a potential hydrocarbon tracer to determine the marine exposure time of crude oil. We employed time course incubations to constrain a time dependent Ra-224 release signature and tested a variety of timescales, temporal resolutions, oil sources, seawater, and experimental treatments to determine potential …

Reinterpreting The Tectonic Model Of The Southern Part Of The Taconic Orogeny Through A Provenance Study Of Late Ordovician Sandstones, Juan Carlos Guerrero

LSU Master's Theses

A provenance study of quartz arenites that stratigraphically are closely associated with major Ordovician K-bentonites has been conducted in order to further our understanding of the tectonic setting of eastern Laurentia during the Late Ordovician. Using laser ablation ICP-MS, detrital zircons separated from Ordovician sandstone samples in the southeastern Appalachian Mountains (Virginia to Alabama) were dated using U-Pb geochronology. Analytical results show three dominate age ranges for the zircons from these sandstones: ~440-490 Ma, ~900-1300 Ma, and ~1300-1500 Ma. In addition, some zircon ages grouped into older ranges of ~1600-1800 Ma, ~1800-1900 Ma, and ~2600-2800 Ma. Zircon ages from ~900-2800 …

Boron Variation And The Subducted Sediment Component In The Volcanics From The Bifurcated Portion Of The Lesser Antilles Island Arc (Laia), Ami Margret Ngo Ward

USF Tampa Graduate Theses and Dissertations

North of Martinique island the Lesser Antilles volcanic arc bifurcates, creating a double arc. Here volcanic activity has migrated up to 50 km westward with time, resulting in two volcanic lines that are distinct in age. The eastern line, commonly referred to as the old arc, was active from Early Eocene to Mid-Miocene (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., 1988). The western line, commonly referred to as the recent arc, has been active since the late Pliocene, ~6 Ma ago (Nagle, 1971; Nagle et al., 1976; Westercamp and Tazieff, 1980; Andreieff et al., …

Exploring Planetary Surfaces With Remote Sensing, Donald R. Hood

LSU Doctoral Dissertations

Aside from Earth, Mars is the most well-explored planetary body in our solar system. Much has been learned about its geologic past including a history of volcanism, ice ages, and potentially long-lasting liquid water. Much of this knowledge of Mars comes from remote observations of the surface and atmosphere from Mars-orbiting satellites. Such remote observations remain the only way to examine the entirety of Mars’ surface as rovers and landers can only examine small areas. The chapters of this work cover three projects that explore the surface of Mars through a variety of remote sensing methods.

In chapter 1, Gamma-ray …

Neogene Chemical Weathering And Provenance Records Of The Western Himalaya Preserved In The Arabian Sea, Peng Zhou

LSU Doctoral Dissertations

Some tectonic models for the Himalaya emphasize the importance of surface processes in controlling the structural evolution. To investigate this tectonic–climatic interactions, and the weathering and erosion of the western Himalaya, International Ocean Discovery Program (IODP) Expedition 355 drilled two sites (site U1456 and U1457) in Laxmi Basin, which located in the Eastern Arabian Sea. In my research project, I plan to use a series of geochemical and geochronological methods on the sediment samples from the cores of these two sites, and sediments from an industrial borehole Indus Marine A-1, which near the Indus river mouth, to reconstruct a climatic …

A Terrestrial Reconstruction Of Gona, Ethiopia Before And During The African Humid Period, Marie N. White, Gary E. Stinchcomb

Posters-at-the-Capitol

The African Humid Period (AHP) resulted in more humid conditions across Northern and Eastern Africa from 15 to 5 thousand years ago (ka). This wetter climate affected flora, fauna and the Homo sapiens living in East Africa. The lack of terrestrial paleoenvironmental reconstructions is a problem in East Africa, especially during the AHP, where most are done utilizing lacustrine or marine proxies. In the case of Gona, Ethiopia, terrestrial proxies are desired due to the rich archaeological and fossil concentrations that occur in the area. Paleosols provide more direct, localized reconstructions that provide context for these finds. This study utilizes …

On The Ablation Of Meteors And The Implications On Organic Delivery To Earth, Christopher Alan Mehta

USF Tampa Graduate Theses and Dissertations

The synthesis of prebiotic organic compounds is a key step in the origin of life. Sources of these materials are divided into endogenous and exogenous sources. Endogenous synthesis—occurring potentially on the surface of the Earth—includes such historic experiments as the Miller spark discharge and formose chemistry. However, one avenue for exogenous synthesis to occur is when meteors enters an atmosphere. Using principles of orbital mechanics, geology, physics, and chemistry, we study meteor ablation and the transport of organic matter to the surface of Earth. To do so, I create numerical models that simulates meteors traveling through the atmosphere of Earth …

Ch. 20 - Deep Carbon Through Deep Time, Robert M. Hazen, Yana Bromberg, Robert T. Downs, Ahmed Eleish, Paul G. Falkowksi, Peter Fox, Eli K. Moore

School of Earth & Environment Departmental Research

This chapter highlights the use of data-driven discovery to address remaining gaps in our understanding of deep carbon.

Influence Of Spring Flow Reversals On Cave Dissolution In A Telogenetic Karst Aquifer, Mammoth Cave, Ky, Chelsey Kipper

Masters Theses & Specialist Projects

An often overlooked connection between karst groundwater systems and surface water is spring flow reversal, the flow of river water into karst springs caused by changes in hydraulic gradient. Karst aquifers are subject to the intrusion of river water when the hydraulic head of a base level river is higher than the hydraulic head of a base level spring. When this occurs, the flow out of the spring reverses, allowing river water to enter base level conduits. River water thus becomes a source of recharge into karst basins, transporting both valuable nutrients and harmful contaminants into karst aquifers. The rapid …

Improving Thorium-230 Determination In Marine Sediment, Katherine Mateos

Independent Study Project (ISP) Collection

Our oceans are intimately related to the climate of our planet. Paleoceanographic approaches aim to study oceans through geologic time to improve models of future climate. Radioisotopes provide us with chemical tracers that help us understand change through time. The uraniumseries decay chain contains thorium-230, a decay product of uranium-234. This isotope is useful to paleoceanographers in its disequilibrium to its parent isotope and in determining the flux of sediment falling to the ocean floor. In order to use 230Th to study oceans, we must be able to accurately measure the amount of thorium in sediment samples. Thorium is found …

Genesis Of Iron And Manganese Sediments In Zoloushka Cave (Ukraine/Moldova) As Revealed By Δ13C Organic Carbon, Piotr Kotula, Viacheslav Andreychouk, Jacek Pawlyta, Leszek Marynowski, Izabela Jendrzejewska

International Journal of Speleology

Zoloushka Cave is one of the largest maze gypsum caves in the world. Mining of the gypsum bedrock and lowering of the water level due to the pumping of groundwater led to exposure of the cave passages to vadose conditions and changed the hydrochemistry of the karst water. As a result, large quantities of Fe and Mn hydroxides were deposited in the passages. It was found that at least two groups of various organisms were involved in depositing ferrous and manganese sediments. In order to establish the mechanism of deposition, we conducted chemical analyses of the sediments and isotopic analyses …

Identification Of Mined Areas That May Contribute To Water Quality Degradation At Hobet Coal Mine, West Virginia, Brian P. Murphy

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.

Oldowan Tool Behaviors Through Time On The Homa Peninsula, Kenya, Emma M. Finestone

Dissertations, Theses, and Capstone Projects

The adaptive significance of tool use to genus Homo is a central theme in human origins. However, what we know from the early Oldowan sites suggests that persistent technology may have begun as an opportunistic behavior with minimal investment, rather than a habitual and widespread adaptive revolution. This dissertation seeks to investigate investment in Oldowan tool production on the Homa Peninsula, Kenya, considering raw material selection, transport, and lithic production at two newly discovered Oldowan localities: Nyayanga (ca. 2.6 Ma) and Sare River (ca. 1.7 Ma).

The first section of this dissertation outlines a method that enables the comparison of …

Environmental Assessment Of Arsenic And Mercury Levels At The Garfield Mill Site, Calico, California, Steven Gregory Thorp

Electronic Theses, Projects, and Dissertations

Environmental impacts of mining at Calico, California, are poorly understood in comparison to the details of its history of silver production. Human health risks associated with arsenic from the lode rock, as well as mercury from the silver milling process, include central nervous system damage, organ failure, and death. To quantify the potential human health risk and manage remediation of this site, tailings from the Garfield Mill site were digitally mapped and chemically analyzed by portable x-ray fluorescence, which permitted volumetric estimates of total mill tailings and the arsenic and mercury budget, as well as identification of anomalies in the …

Organic/Inorganic Interfacial Interactions Affecting Metal Reactivity: Water Treatment And Sensor Applications, Mohamed Nabil Shaikh

Civil Engineering ETDs

The aim of this dissertation was to investigate the interactions occurring at the organic – inorganic interface between solid media and aqueous contaminants for water treatment and sensor applications. The gaps in current literature on these interfacial organic-inorganic interactions must be bridged in order to develop advanced water treatment and monitoring technologies for improving water quality and thus, restore and protect the contaminated water resources. As a part of this dissertation, manganese oxides-based composites and electrospun polymer mats were developed and investigated for gaining mechanistic insights of organic (bisphenol A and acetaminophen) and inorganic (uranium) contaminants removal, respectively. These reactions …

Assessing Diagenetic Conditions In The Late Triassic Chinle Formation Through Petrographic And Geochemical Analysis Of Phytosaur Teeth, John Fortner

Earth Sciences Theses and Dissertations

The Upper Triassic (Norian; ~227-208 Ma) Chinle Formation of Petrified Forest (PeFo) National Park was deposited during a time of major tectonic breakup and profound changes in atmospheric circulation and faunal compositions. Little has been done however to assess whether surficial paleoenvironmental trends related to deterioration of the Late Triassic Megamonsoon resulted in similar trends in the early diagenetic environment. Here, we use phytosaur tooth dentin as a proxy for diagenetic conditions in the Chinle of PEFO, as its greater susceptibility to chemical alteration relative to enamel makes it an excellent substrate from which changing diagenetic conditions may be studied …

Fluid-Mobile Trace Element Variability Of Serpentinites And Entrained Crustal Rocks Across The Mariana Forearc System, Raymond M. Johnston

USF Tampa Graduate Theses and Dissertations

In the Mariana subduction system, active serpentinite mud volcanoes are associated with the subduction of the Pacific plate beneath the Philippine plate in a non-accretionary convergent plate margin. This location offers a unique opportunity to study the subduction zone interface with little crustal contamination. The systematics of fluid-mobile trace elements (FME) (As, Cs, Rb, Sb, Tl, Pb, and Sr) in erupted serpentinite muds and entrained serpentinized ultramafic and mafic clasts can place constraints on the release of slab-derived fluids from the downgoing plate, and ultimately the pressure/temperature (P/TC°) conditions at which these fluids are mobilized.

The samples analyzed in this …

A Metasomatized Lithospheric Mantle Control On The Metallogenic Signature Of Post-Subduction Magmatism, David A. Holwell, Marco Fiorentini, Iain Mcdonald, Yongjun Lu, Andrea Giuliani, Daniel J. Smith, Manuel Keith, Marek Locmelis

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Ore deposits are loci on Earth where energy and mass flux are greatly enhanced and focussed, acting as magnifying lenses into metal transport, fractionation and concentration mechanisms through the lithosphere. Here we show that the metallogenic architecture of the lithosphere is illuminated by the geochemical signatures of metasomatised mantle rocks and post-subduction magmatic-hydrothermal mineral systems. Our data reveal that anomalously gold and tellurium rich magmatic sulfides in mantle-derived magmas emplaced in the lower crust share a common metallogenic signature with upper crustal porphyry-epithermal ore systems. We propose that a trans-lithospheric continuum exists whereby post-subduction magmas transporting metal-rich sulfide cargoes play …

Biogeochemical Controls Of Surface Ocean Phosphate, Adam C. Martiny, Michael W. Lomas, Weiwei Fu, Philip W. Boyd, Yuh-Ling L. Chen, Gregory A. Cutter, Michael J. Ellwood, Ken Furuya, Fuminori Hasshihama, Jota Kanda, David M. Karl, Taketoshi Kodama, Qian P. Li, Jian Ma, Thierry Moutin, E. Malcolm S. Woodward, J. Keith Moore

OES Faculty Publications

Surface ocean phosphate is commonly below the standard analytical detection limits, leading to an incomplete picture of the global variation and biogeochemical role of phosphate. A global compilation of phosphate measured using high-sensitivity methods revealed several previously unrecognized low-phosphate areas and clear regional differences. Both observational climatologies and Earth system models (ESMs) systematically overestimated surface phosphate. Furthermore, ESMs misrepresented the relationships between phosphate, phytoplankton biomass, and primary productivity. Atmospheric iron input and nitrogen fixation are known important controls on surface phosphate, but model simulations showed that differences in the iron-to-macronutrient ratio in the vertical nutrient supply and surface lateral transport …

Supporting Dataset For Chloride Source Delineation In An Urban-Agricultural Watershed, Deicing Agents Versus Agricultural Contributions, Eric Wade Peterson, Andrew Oberhelman

Faculty Publications - Geography, Geology, and the Environment

Analyses (n = 535) of chloride (Cl^-), bromide (Br^-), nitrate as nitrogen (NO₃-N), sodium (Na⁺), calcium (Ca²⁺), and potassium (K⁺) in stream water, tile-drain water, and groundwater were conducted in an urban-agricultural watershed (10% urban/impervious, 87% agriculture) to explore potential differences in the signature of Cl^- originating from an urban source as compared to an agricultural source. Water samples were collected on a weekly interval from February 2018 to February 2019 at three station along the stream and from tile drains and wells. Nearly all surface water …

Assessing Bioavailability, Metal Fractionation, Magnetic Susceptibility, And Organic Matter Interactivity In Mine-Waste Contaminated Sediments In Turkey Creek, Joplin, Missouri, Zachary Joseph Collette

Graduate Theses/Dissertations

Joplin, Missouri, part of the Tri-State Mining District (TSMD), has a long history of mining that resulted in mine waste piles proximal to the mines throughout the area. A local lead smelter also resulted in smelter fallout in Joplin. Mine waste pile runoff and local smelter fallout resulted in contamination of sediments, soils, and waterways. In the 1990s, remediation of residential soils and play areas began after blood lead levels in children were much higher than the national average. Soon afterwards, the chat piles were removed and used for beneficial reuse purposes. In May of 2011, an EF5 tornado devastated …

Insights Into The Evolution Of The Galápagos Archipelago And Its Mantle Source From Monogenetic Near-Island Seamounts, Darin M. Schwartz

Boise State University Theses and Dissertations

Lavas erupted at ocean island volcanoes are classically used as probes of the deep Earth, with ultimate goals of discerning the compositional heterogeneity, structure and dynamics of the Earth’s mantle. However, sampling restricted to volcanic islands and large, submarine volcanic constructs alone likely results in limited spatial resolution of the mantle’s composition and structure, owing to homogenization in sub-island magma reservoirs. Further, islands provide poor temporal resolution given that their multigenetic construction can overprint any time progressive chemical variations and they subside with age making detailed sampling difficult. For my dissertation I investigate whether seamounts surrounding islands in the Galápagos …

Stable Isotope And Geochemical Characterization Of Nutrient Sources In The Big Creek Watershed Of Northwest Arkansas, Kelly Robin Sokolosky

Graduate Theses and Dissertations

The establishment of a concentrated animal-feeding operation (CAFO) in Newton County, Arkansas near Big Creek, a tributary of the Buffalo National River, has raised concern over potential degradation of water-quality in the watershed. In this study, isotopic tools were combined with standard geochemical approaches to characterize nutrient sources and dynamics in Big Creek. An isotopic and geochemical reference library of potential nutrient sources in the Big Creek watershed was established by direct sampling of representative potential sources, including septic-system effluent, poultry litter, swine and cattle manure, and CAFO waste lagoons. Representative nutrient sources and Big Creek stream samples were analyzed …

Provenance And Maximum Depositional Age Analysis Of The Moenave Formation Using Detrital Zircon U-Pb Geochronology And Sandstone Petrography, Asher Rea Boudreaux

Graduate Theses and Dissertations

In southwestern Utah and northeastern Arizona, Moenave Formation (latest Triassic(?)-Jurassic) is bracketed by well-studied Mesozoic units extensively sampled for detrital zircon geochronology and is poorly documented in regard to provenance, representing an important gap in knowledge. The Moenave Formation provides a unique opportunity to employ detrital zircon U-Pb geochronology and sandstone petrography relevant to completing the paleogeographic, evolutionary, and climatic story of the region. This study aims to characterize the sedimentary provenance of the Moenave Formation and to identify, or at least improve constraints on, the stratigraphic position of the Triassic-Jurassic boundary (TJB) and placement of the end-Triassic extinction (ETE), …

The Paleozoic Sedimentary Rocks Of The Ouachita Mountains And Their Genetic Relationship To The Mississippi Valley-Type Mineralization In The Southern Ozark Region: Insights From Radiogenic Pb Isotopes And Trace Elements Studies, Christophe Wakamya Simbo

Graduate Theses and Dissertations

Cluster of Pb and/or Zn deposits of the well-known Tri-State and Northern Arkansas Mississippi Valley Type (MVT) districts located north of the Arkoma basin and the Ouachita fold-thrust belt in north America are genetically connected to the Pennsylvanian-Permian Ouachita orogeny which triggered a South-North topographic gradient flow of basinal brines, leaching metal rich sediments en route. The objective of the research is twofold. First, to ascertain whether the organic-rich shales and sandstones from the study area provided metals during the mineralization event, which was coeval with the Ouachita orogeny. Second, to assess the depositional environment of the potential source rocks, …

Constraining The Oxygen Values Of The Late Cretaceous Western Interior Seaway Using Marine Bivalves, Camille H. Dwyer

Earth and Planetary Sciences ETDs

The Western Interior Seaway (WIS) remains an oceanographic enigma, including its circulation, similarity to the open ocean, and the fidelity of geochemical proxies to reconstruct paleoenvironments. Across the late Campanian and early Maastrichtian I test whether: 1) the WIS had unique δ¹⁸O_VPDB compared to other marine settings, 2) increasing oceanographic restriction changed the stable isotope composition, and 3) biases, e.g., taxonomy or diagenesis, influenced stable isotope compositions. Results indicate distinct δ¹⁸O_VPDB in the WIS compared to other marine settings. δ¹⁸O_VPDB values were stable through time, suggesting insignificant oceanographic restriction and a …

Natural Salinization Of The Jemez River, New Mexico: An Insight From Trace Element Geochemistry, Jon K. Golla

Earth and Planetary Sciences ETDs

The Jemez River, a tributary of the Rio Grande in north-central New Mexico, receives thermal water input from the geofluids of the Valles Caldera, an active, high-temperature, liquid-dominated geothermal system. We focus on a ∼50-km portion of the northern Jemez River. This research extends previous decadal work (Crossey et al., in prep., 2013) on major chemistry in the river by characterizing the response of 16 trace elements to geochemical contributions from geothermal waters (McCauley, Spence, Soda Dam, and Jemez Springs springs and San Ysidro mineral waters), an area with copious hydrothermal degassing (Hummingbird), and two major tributaries (Rio San Antonio …

Identifying Characteristics Of Actionable Science For Drought Planning And Adaptation, Adam Wilke, Amanda Cravens

United States Geological Survey: Publications

Changing climate conditions can make water management planning and drought preparedness decisions more complicated than ever before. Federal and State natural resource managers can no longer rely solely on historical trends as a baseline and thus are in need of science that is relevant to their specific needs to inform important planning decisions. Questions remain, however, regarding the most effective and efficient methods for extending scientific knowledge and products into management and decision-making. This project analyzed two unique cases of water management to better understand how science can be translated into resource management actions and decision-making, focusing particularly on how …