Geochemistry Commons^™

A New Method For Ultra-Low Sulfate Extraction And A Pilot Study In Arid Soils, Marisela Montelongo

Open Access Theses & Dissertations

Sulfur in soils is a crucial nutrient for all organisms including plants. Sulfate (SO42-), a water soluable anion, is a good source of this important element. Because of the importance of sulfur for agriculture, the use of sulfate has been well studied in temperate climate zones, and it is generally accepted that microbes play a critical role in controlling the availability of sulfate. Organically bound sulfur, such as sulfate esters and carbon-bonded sulfur, compounds that are generated and decomposed by microbes, are essential sulfur sources for plants under these conditions. For arid environments, knowledge of sulfate turnover in soils by …

Tracing Anthropogenic Salinity Inputs To The Semi-Arid Rio Grande River: A Multi-Isotope Tracer Approach, Sandra Garcia

Open Access Theses & Dissertations

Water is an important component for life and as such water quality and availability are major concerns in the world today. In arid to semi-arid regions, freshwater quality is especially important due to its scarcity. Elevated salinity of rivers in arid regions poses potentially devastating consequences for the communities that depend on these rivers as a source of freshwater. In the Rio Grande region, high salinity has led to severe reductions in crop productivity and accumulation of salts in soils. Salinity inputs into the river may come from both anthropogenic and natural sources. Thus, identifying and quantifying salinity inputs to …

Gypsum, Calcite, And Dolomite Caprock Fabrics And Geochemistry From The Gypsum Valley Salt Diapir, Paradox Basin, Southwestern Colorado, Kevin Lerer

Open Access Theses & Dissertations

Caprocks are found on top of or in a lateral position relative to salt diapirs. The caprocks predominantly comprise sulfate minerals such as anhydrite or gypsum, which presumably accreted during the dissolution of salt from evaporite sediments. In some cases, the sulfate minerals are replaced by carbonate minerals, referred to as "carbonate caprock". Carbonate caprocks associated with salt diapirs are important because they can act as reservoirs or conduits for hydrocarbons, and because they can be easily misidentified as carbonate lithologies belonging to the stratigraphy of the sedimentary sequences adjacent to the diapir, which can jeopardize the accurate interpretation of …

Archived Rock Samples From Jane Selverstone's Research Collection, Jane Selverstone

Earth and Planetary Sciences Faculty and Staff Publications

This Excel spreadsheet lists all of the rock samples from Jane Selverstone's research collection that have been archived into the Earth and Planetary Sciences Collections at the University of New Mexico. All samples are listed by original (published) sample number and by an affiliated International GeoSample Number. Samples are grouped by research project, and doi information is given for all publications resulting from work on each project. Rock samples include various combinations of hand specimens, powders, thin sections, and billets from which thin sections were prepared. Information is included to identify the drawers within which each sample can be found …

Effects Of Nonaerated Circulation Water Velocity On Nutrient Release From Aquaculture Pond Sediments, Xiangju Cheng, Dantong Zhu, Xixi Wang, Deguang Yu, Jun Xie

Civil & Environmental Engineering Faculty Publications

Sustaining good water quality in aquaculture ponds is vital. Without an aerator, the dissolved oxygen in ponds comes primarily from mass transfer at the water-ambient atmosphere interface. As sediment can seriously affect water quality, this study used indoor experiments to examine the nutrient (nitrogen and phosphorus) release mechanisms and fluxes from sediment in aquaculture ponds with moving water but no aeration. The results showed that the ammonia nitrogen (NH₃-N) concentration in the overlying water was inversely proportional to flow velocity and that a higher flow velocity tended to result in a lower concentration in the overlying water, a …

Community Production Modulates Coral Reef Ph And The Sensitivity Of Ecosystem Calcification To Ocean Acidification, Thomas M. Decarlo, Anne L. Cohen, George T. F. Wong, Fuh-Kwo Shiah, Steven J. Lentz, Kristen A. Davis, Kathryn E. F. Shamberger, Pat Lohmann

OES Faculty Publications

Coral reefs are built of calcium carbonate (CaCO₃) produced biogenically by a diversity of calcifying plants, animals, and microbes. As the ocean warms and acidifies, there is mounting concern that declining calcification rates could shift coral reef CaCO3 budgets from net accretion to net dissolution. We quantified net ecosystem calcification (NEC) and production (NEP) on Dongsha Atoll, northern South China Sea, over a 2 week period that included a transient bleaching event. Peak daytime pH on the wide, shallow reef flat during the nonbleaching period was ~8.5, significantly elevated above that of the surrounding open ocean (~8.0-8.1) as …

Spatial Patterns Of Sea Level Variability Associated With Natural Internal Climate Modes, Weiqing Han, Gerald A. Meehl, Detlef Stammer, Aixue Hu, Benjamin Hamlington, Jessica Kenigson, Hindumathi Palanisamy, Philip Thompson

OES Faculty Publications

Sea level rise (SLR) can exert significant stress on highly populated coastal societies and low-lying island countries around the world. Because of this, there is huge societal demand for improved decadal predictions and future projections of SLR, particularly on a local scale along coastlines. Regionally, sea level variations can deviate considerably from the global mean due to various geophysical processes. These include changes of ocean circulations, which partially can be attributed to natural, internal modes of variability in the complex Earth's climate system. Anthropogenic influence may also contribute to regional sea level variations. Separating the effects of natural climate modes …

Geothermometry Of Two Cascade Geothermal Systems, Donnel Alexander Malkemus

Dissertations and Theses

For this thesis I applied classical and multi-component geothermometry techniques to new water chemistry data from Breitenbush Hot Springs, Oregon and the Wind River Valley, Washington. A total of 20 well, spring, and stream samples from Breitenbush Hot Springs and 4 spring samples from the Wind River Valley were collected and analyzed for major, minor, and select trace anions and cations, as well as stable oxygen and hydrogen isotopes. I used two computer programs, GeoT and RTEst, to conduct multi-component geothermometry reservoir condition estimation on each water sample. Water chemistry data from Breitenbush Hot Springs indicates a range of thermal, …

Characterizing Crystal Populations For The Petrogenesis Of The Post-Collapse Rhyolites In The Long Valley Caldera, California, William Joseph

UNLV Theses, Dissertations, Professional Papers, and Capstones

Post-collapse rhyolites of the Long Valley in eastern California are the product of remelting of crystal mush bodies via mafic rejuvenation following the eruption of the Bishop Tuff. This is supported by mineral textures and major element geochemistry from the Resurgent Dome rhyolite, the Moat rhyolite, the Hot Creek Flow, and the Deer Mountain rhyolite. New 40Ar/39Ar eruptive ages are reported for the Moat rhyolites (525 ka, 333 ka, 118 – 94 ka), Hot Creek Flow (312 – 295 ka), and the Deer Mountain rhyolite (65 ka). The initial post-collapse eruptions, resulting in the Resurgent Dome rhyolite, appear to be …

Temporal Co2 Variations And The Influence Of Bat Colonies In Speleogenesis: Continuous Co2 Monitoring In War Eagle Cavern, Arkansas, Ginny Sue Holcomb

Graduate Theses and Dissertations

Dissolved concentrations of CO2 in a karst aquifer are a major control on calcite dissolutional processes, as CO2 combines chemically with water to form carbonic acid. As increasing amounts of CO2 are added to the system, greater resultant water aggressivity generates greater rates of dissolution. Spatial and temporal variations in carbon flux through the system may occur over a range of time scales, and high-resolution data collection is needed to truly understand and characterize such variability. Continuous CO2 monitoring in War Eagle Cavern, Arkansas, will suggest a number of influential parameters with varying degrees of importance throughout an annual cycle. …

Characterization Of Rare Earth Elements In Weathered Coal Combustion Products, Brendon Gordon Tucker

Theses and Dissertations

The economic interest in Rare Earth Elements (REEs) has directed research into the REE content of fresh Combustion Products (CCPs). CCPs are the solid waste produced by coal combustion, which have been noted to weather rapidly in holding ponds to clays that are known to bind up REEs. Sequential leaching experiments using a modified version of Tessier et al. 1979 method were performed to determine the chemical association of the REE content in fresh and weathered CCPs. The leachate of each step was analyzed through ICPMS to determine the REE content in each fraction of the CCP material. Morphological changes …

Synthesis And Carbonation Of Nanocrystalline Fayalite (Fe2sio4), Joshua Manley

Theses and Dissertations

The limited availability of fayalite on Earth has led to the use of synthetic fayalite in studies requiring iron rich olivine. The method presented in Part II is a novel modification of previous sol-gel techniques that produced nanofayalite. This new method uses a different set of reactants that eliminates several steps from the previous method, thus saving time while producing a similar result. Presented in Part III is a scoping experiment investigating carbonation of nanofayalite using slight modification from techniques of previous studies involving nanoforsterite. No previous studies have examined the carbonation of nanofayalite. While it is expected that experimental …

Using Geochemistry And Strontium Isotopic Ratios (87sr/86sr) To Determining Water Mixing And Sources In The Picher Mining District, William Daniel Ketcheside

Theses and Dissertations

The mining of lead and zinc ores in the Tri-State Mining District of Kansas, Missouri, and Oklahoma resulted in some of the most severe environmental degradation in the country. Large amounts of waste rock, known as ‘chat’, were produced during mining and left in surface piles in the surrounding area. These chat piles, located mostly near the town of Picher, Oklahoma contain potentially harmful elements that can be leached from the rock into local streams and sediment. The mines also filled with water after mining ceased and have discharged contaminated water to nearby waterways, as well as resulted in groundwater …

Record Of Massive Upwellings From The Pacific Large Low Shear Velocity Province, Pilar Madrigal, Esteban Gazel, Kennet E. Flores, Michael Bizimis, Brian Jicha

Faculty Publications

Large igneous provinces, as the surface expression of deep mantle processes, play a key role in the evolution of the planet. Here we analyse the geochemical record and timing of the Pacific Ocean Large Igneous Provinces and preserved accreted terranes to reconstruct the history of pulses of mantle plume upwellings and their relation with a deep-rooted source like the Pacific large low-shear velocity Province during the Mid-Jurassic to Upper Cretaceous. Petrological modelling and geochemical data suggest the need of interaction between these deep-rooted upwellings and mid-ocean ridges in pulses separated by ∼10–20 Ma, to generate the massive volumes of melt …

Abrupt Ocean Anoxia During The Late Ordovician Mass Extinction Detected Using Uranium Isotopes Of Marine Carbonates, Rickey Bartlett, Maya Elrick, Yemane Asmerom, Viorel Atudorei

Earth and Planetary Sciences ETDs

The Ordovician witnessed an explosion in marine biodiversity punctuated by the first of the ‘big-5’ Phanerozoic mass extinctions, the Late Ordovician mass extinction (LOME). The LOME consists of two discrete pulses occurring at the beginning and end of the Hirnantian. Lithologic and geochemical evidence suggests widespread marine anoxia triggered the second LOME pulse; however, most of these redox proxies record local bottom water or porewater conditions rather than global seawater conditions. To evaluate global redox trends, we utilize uranium (U) isotopes and trace element geochemistry of marine carbonates as a global marine redox proxy.

Bulk carbonate samples were collected from …

Abundance Of Archaias Angulatus On The West Florida Coast Indicates The Influence Of Carbonate Alkalinity Over Salinity, Sean Thomas Beckwith

USF Tampa Graduate Theses and Dissertations

Archaias angulatus, a large symbiont-bearing foraminifer (Order Miliolida) that produces a Mg-calcite shell, is common throughout the Caribbean and warm western Atlantic region. This species lives abundantly in seagrass beds along the Springs Coast of northwest Florida (up to 4 adults per gram of sediment) where spring-fed rivers emerge from a limestone aquifer, and in Florida Bay to the southeast (25 adults/g) where the sediment is primarily biogenic carbonate. In contrast, live specimens are seldom found in the seagrass beds along the central-west coast of Florida, where barrier islands are dominated by quartz sand. My working hypothesis is that substratum …

A Complex Legacy Of Contamination In Urban Estuarine Systems, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Industrialized urban waterways have typically suffered decades of contamination, varying in source and intensity as manufacturing and transportation practices evolved. The U.S. Environmental Protection Agency designates locales with particularly severe contamination as Superfund sites. Among these, the Gowanus Canal and lower Passaic River in the New York/New Jersey harbor estuary illustrate a complex range of contamination types.

The 2.2 km Gowanus Canal, with sluggish circulation driven mostly by tides, accumulated fine-grained sediments (average thickness of 3 m) highly enriched in organic carbon (OC, mean 11 % but up to 49 %) derived from hydrocarbons, sewage, coal, char, and biomass, along …

Surficial Geology Of York College Campus (Queens) And Montauk Point (Long Island): An Open Access To Geoscience Education, Nazrul I. Khandaker, Stanley Schleifer, Krishna Mahabir, Erik Menjivar, Ality Aghedo, Dennis Baidoo, Tenzin Choeying, Vanessa Erwin, Jonathan Xavier, Laboni Molla, Akeed Alrubay

Publications and Research

To evaluate compositional and textural differences among the samples collected from York College (YC) campus (Queens), Montauk Point (MP) and Hither Hills (HH), Long Island, emphasis is given to the general geologic setting, overall grain size distribution, and relative abundances of light and heavy mineral assemblages. Geologic setting encompasses outwash plains (York College), fluvioglacial and glacial (Montauk Point) and beach and dune complex (Hither Hills). YC samples were collected from depth ranging 40 cm to 250 cm and are mostly an assortment of medium to coarse sand, granule to cobble sized, minor silt, and clay. Presence of low angle cross …

Compositional Diversity In Arcs: A Record Of Magmatic Processes In The Peru Coastal Batholith, Ica, Ana Maria Martinez Ardila

Loma Linda University Electronic Theses, Dissertations & Projects

Peruvian granitic plutons display evidence for crustal recycling and magma mixing. Evidence of physical and chemical processes operating during the formation of the Ica-Pisco complexes involves magma mixing and mingling as result of felsic and mafic interactions. Evidence of crustal recycling was identified from kilometer-scale cauldron subsidence, meter and centimeter-scale -stoping, and disaggregation. At the petrographic microscope scale, evidence for recycling and mixing between mantle and crustal magma during crystallization is found from disequilibrium features such as reaction rims, resorbed cores, and patchy zoning. Elemental and isotope geochemistry data indicate that mantle magmas have incorporated continental crust material from varying …

Interpreting Southern California Arc Geochemistry By Multivariate And Spatial Methods, Lance R. Pompe

Loma Linda University Electronic Theses, Dissertations & Projects

Exploratory data analysis methods of multivariate statistical techniques and spatial visualization are emerging trends in understanding big datasets. In this project, these techniques are applied to a large igneous geochemical dataset from the southern California segment of the Mesozoic Cordilleran arc to better understand magmatic and plate tectonic processes at a subduction zone. A set of 287 granitic samples collected by Baird and Miesch (1984) from the Peninsular Ranges batholith is analyzed for 38 geochemical elements. Patterns in both the geochemical variation and the spatial variation of this dataset are explored. Since geochemical data are compositional in nature, special treatment …