Geochemistry Commons^™

The Impact Of Sulfide Mineral Weathering On The Isotopic Signatures Of Fe And Cu In Metal-Rich Streams, Ana Lourdes Gutierrez

Open Access Theses & Dissertations

The oxidative weathering of sulfide minerals, like pyrite, at the Earth's surface controls the formation of acid mine drainage sites as well as the Fe isotope composition of these areas and the main processes taken place. In this study, water and rock samples were collected from acidic drainages (most from abandoned mining sites) from the St. Juan Mountains in Colorado. The water samples were measured in-situ for dissolved oxygen, dissolved Fe(II), pH, and conductivity. Filtered acidified, unfiltered acidified, and Fe-oxide samples were analyzed for their metal concentrations. Ion-exchange chromatography was applied to both water and digested oxide fractions in order …

The Vinylguaiacol/Indole Or Vgi ("Veggie") Ratio: A Novel Molecular Parameter To Evaluate The Relative Contributions Of Terrestrial And Aquatic Organic Matter To Sediments., Michael A. Kruge, Kevin K. Olsen, Jaroslaw W. Slusarczyk, Elaine Gomez

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The organic matter (OM) fraction of estuarine sediments is often distinctive and thus diagnostically useful in determinations of sedimentary provenance. Among the most fundamental distinctions to be made is that between terrestrial and aquatic OM. To supplement the parameters commonly used for this purpose (e.g., C/N and stable isotope ratios), we proposed the Vinylguaiacol/Indole or VGI ("Veggie") ratio, defined as [vinylguaiacol / (indole + vinylguaiacol)] using data produced by analytical pyrolysis-gas chromatography/mass spectrometry of dried, homogenized sediment samples. The ratio employs the peak areas of these two compounds on the mass chromatograms of their molecular ions (m/z 150 and 117). …

Policy And Science Of Geothermal Heat Use At Mcmurdo Station, Antarctica, Joe Alvine

Department of Environmental Studies: Undergraduate Student Theses

My thesis research project deals with the use of geothermal heat in Antarctica. Currently it is not allowed due to article 7 of the 1991 Protocol on Environmental Protection that placed a 50 moratorium on the exploitation of mineral resources. The US main base in Antarctica, McMurdo Station is currently powered by diesel generators that are inefficient, cause environmental damage, and is expensive to run. By exploring alternative energy options, McMurdo Station can reduce its dependence on non-renewable energy sources. By determining the geothermal potential of McMurdo Station, this project explores the possibilities and benefits that would occur with the …

Linkage Of Asteroids And Meteorites By The Study Of Terrestrial Analogs, Daniel Robert Ostrowski

Graduate Theses and Dissertations

Asteroids are one group of the bodies that can provide insights into the origin and early history of the solar system. Asteroids are considered to be fairly pristine, with alterations only occurring to their surface from the space environment. Studying them provides opportunities to learn about the primordial solar system, its materials, and processes and how it evolved into the current condition. Many asteroids have been discovered, but few have their surface compositions determined. The C and X complexes provide a difficulty in determination because their near infrared spectrum is featureless.

The C asteroids have been long associated with the …

Heavy Metal Concentrations In Water And Surface Sediments Of Wilgreen Lake, Madison County, Kentucky, Chad Von Gruenigen, Walter S. Borowski

EKU Faculty and Staff Scholarship

Heavy metal pollution remains problematic in natural waters, particularly for localities near plausible anthropogenic sources. We assayed the level of heavy metals in surface waters and within surface sediments of Wilgreen Lake, whose watershed drains industrial, urban, agricultural, and residential areas near Richmond, Kentucky. Water samples were treated according to Environmental Protection Agency (EPA) protocols and digested with trace-metal-grade nitric and hydrochloric acids. Sediment samples were collected with a grab sampler and digested using established EPA procedures with hydrogen peroxide and trace-metal-grade nitric acid. Both water samples and sediment samples were sent to Activation Laboratories for analysis, and were measured …

Carbon Isotopic Fractionation Across A Late Cambrian Carbonate Platform: A Regional Response To The Spice Event As Recorded In The Great Basin, Jonathan Lloyd Baker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Geochemical models have suggested that the late Cambrian was characterized by a greenhouse climate with high pCO2. Furthermore, stableisotope analyses within the Great Basin have documented a large carbonate isotope (δ13Ccarb) excursion, known as the Steptoean Positive Carbon Isotope Excursion (SPICE). This event has been documented globally, and is interpreted as having resulted from enhanced organic carbon burial. Unless the size of carbon reservoirs in the Cambrian ocean was significantly different from those of the Cenozoic, this forcing should have resulted in a comparable carbon-isotope excursion in organic matter (δ13Corg). It is also predicted that increased organic carbon burial would …

Sequence And Chemostratigraphy Of The Middle Cambrian Succession In Nevada And Utah, Robyn A. Howley

UNLV Theses, Dissertations, Professional Papers, and Capstones

The House Range Embayment of western Utah and eastern Nevada was a prominent topographic feature on the passive margin of western North America during the middle and late Cambrian. In this study, detailed documentation of sequence boundaries, and their intervening sequences across a platform-to-basin transect of the House Range Embayment was used to establish a sequence-stratigraphic framework from which the depositional history of the embayment was deciphered. This framework was then used to test the hypothesis that the House Range Embayment formed by tectonic subsidence. In addition, the chemostratigraphic (δ13Ccarb) record across the embayment was analyzed within this framework to …

Age And Petrogenesis Of The Roaring Mountain Rhyolites, Yellowstone Volcanic Field, Wyoming, Kathleen Marie Wooton

UNLV Theses, Dissertations, Professional Papers, and Capstones

Extracaldera rhyolites in the Norris-Mammoth Corridor of the Yellowstone Volcanic Field (YVF) appear to be unrelated to intracaldera volcanism, resulting instead from a new crustal magma source derived from northeastward propagation of the Yellowstone “melting anomaly.” The youngest extracaldera rhyolite unit, the Roaring Mountain Member (RM), is chemically distinct from the previous extracaldera lavas, reverting to more primitive compositions.

This study suggests that the majority of the RM rhyolites erupted from the same large-scale silicic magma system. Based on geochemistry and 40Ar/39Ar geochronology, the Crystal Spring mingled rhyolite and Obsidian Cliff rhyolite erupted concurrently at 59.1 ± 2.0 ka. The …

Heavy Metal Concentrations In Water And Surface Sediments Of Wilgreen Lake, Madison County, Kentucky, Chad Von Gruenigen, Walter S. Borowski

EKU Faculty and Staff Scholarship

Heavy metal pollution remains a problem in natural waters, particularly for localities near plausible anthropogenic sources. We assayed the level of heavy metals in surface waters and within surface sediments of Wilgreen Lake, whose watershed drains industrial, urban, and residential areas near Richmond, Kentucky.

Water samples were treated according to Environmental Protection Agency (EPA) protocols and digested with trace-metal-grade nitric and hydrochloric acids. Sediment samples were collected with a grab sampler and digested using established EPA procedures with hydrogen peroxide and trace-metal-grade nitric acid. Both water samples and sediment samples were sent to Activation Laboratories for analysis, and were measured …

Patterns Of Heavy Metal Concentration In Core Sediments, Wilgreen Lake, Madison County, Kentucky, Clint Mcmaine, Walter S. Borowski

EKU Faculty and Staff Scholarship

Elevated levels of cadmium, copper, lead, and nickel were found within the waters of Wilgreen Lake during a preliminary survey in 2007. Accumulation of heavy metals in freshwater systems is a known problem. Heavy metals enter the lake in the dissolved phase or adsorbed onto sediment particles and may be linked to industries within the lake’s watershed. Under certain geochemical conditions such as anoxia, heavy metals may detach from sediment particles and diffuse into overlying lake waters, causing a renewed influx of heavy metals into the ecosystem. We hypothesize that heavy metals should decrease in concentration upcore as a result …

Upper Cretaceous Peay Bentonites (North-Central Wyoming): Provenance And Tectonics Interpretation From Ash Composition, Nazrul I. Khandaker, Carl F. Vondra, Karl E. Seifert, Malek Shami, Rochelle Cardinale, Thakur Chaturgan

Publications and Research

The Peay bentonites belong to the basal Frontier Formation (Bighorn Basin, north-central Wyoming), primarily outcrop in the Bighorn Basin, rest on an extensively bioturbated sandstone unit, the Peay Sandstone, and are generally the thinner bentonitic unit. Beds of very light gray to greenish gray bentonite are also abundant in the lower Frontier units between Kaycee and Mayoworth (Powder River Basin) and are very rarely as much as 3 m thick. Bentonite occurs within the interstratified shale, sandstone, and siltstone sequences of the lower Frontier unit throughout much of the southwestern Powder River Basin. The purpose of this study is to …

Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Comparison Of Ice Core Dissolved Organic Matter From A Greenland Ice Core By Nanospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Joshua Jeremiah Shiloh Marsh

Chemistry & Biochemistry Theses & Dissertations

Recent studies of ice cores have embarked on the task of determining the classes of dissolved organic matter (DOM) present in melt-water from the cores collected in numerous locations in the northern and southern hemispheres. This DOM originally derives from wet precipitation and is thought to reflect atmospheric organic matter derived from anthropogenic and non-anthropogenic sources. Because the amount of DOM is so low, previous studies have necessarily used large sample volumes (greater than 500 mL) to concentrate sufficient ice core DOM necessary for mass spectral analysis. Solid phase extraction (SPE) with C₁₈ resins was followed by evaporative concentration …

Geochemistry Of Pyrite And Whole Rock Samples From The Getchell Carlin–Type Gold Deposit, Humboldt County, Nevada, Tim A. Howell, Jean S. Cline

Undergraduate Research Opportunities Program (UROP)

Carlin-type gold deposits were not recognized as a new major type of gold deposit until the 1960’s. The Getchell deposit, which is now known to be a Carlin-type gold deposit, was discovered in 1934 (Joralemon, 1951). This deposit is located in north central Nevada (Fig. 1). Much is known about the physical characteristics of Carlin-type gold deposits (Cline et al., 2005). An unusual characteristic of these deposits is that free gold is generally not present. Instead, gold occurs as sub-micrometer particles in the mineral pyrite or marcasite. The marcasite and pyrite that are gold bearing commonly occur as rims on …

Secondary Enrichment Of Copper At The Madison Gold Skarn Deposit, Silver Star District, Montana, Christopher H. Gammons, Jill Sotendahl, Dan Everett

Geological Engineering

Secondary Enrichment of Copper at the Madison Gold Skarn Deposit, Silver Star District, Montana. This paper focuses on the chemical reactions responsible for secondary enrichment of copper...we argue that most of the secondary Cu enrichment occurred during a late hydrothermal event that replaced the high temperature skarn mineral assemblage with hematitic jasperoid. Evidence favoring this "hypogene" Cu enrichment hypothesis is presented.

Thermal History Of The Ecstall Pluton From 40Ar/39Ar Geochronology And Thermal Modeling, Sarah J. Brownlee, Paul R. Renne

Environmental Science and Geology Faculty Research Publications

New ⁴⁰Ar/³⁹Ar thermochronology results and thermal modeling support the hypothesis of Hollister et al. (2004), that reheating of the mid-Cretaceous Ecstall pluton by intrusion of the Coast Mountains Batholith (CMB) was responsible for spatially variable remagnetization of the Ecstall pluton. ⁴⁰Ar/³⁹Ar ages from hornblende and biotite from 12 locations along the Skeena River across the northern part of the Ecstall pluton decrease with proximity to the Quottoon plutonic complex, the nearest member of the CMB to the Ecstall pluton. The oldest ⁴⁰Ar/³⁹Ar ages are found farthest from the Quottoon plutonic …

Identification Of Geochemical Facies Through Major Ion Data And Additional Parameters From Shallow Groundwater Utilizing A Comparison Of Geomathematics And Traditional Methods In Las Vegas Valley, Nevada, Eric Dano

UNLV Theses, Dissertations, Professional Papers, and Capstones

There has been little exploration to identify geochemical facies in shallow groundwater in the Las Vegas Valley in Clark County, Nevada. Identification of hydrochemical facies in Las Vegas Valley is important for assessing the extent and nature of a potential groundwater resource. The identification of facies could be complicated by the possibility that secondary recharge constitutes a hydrochemical facies of its own. To identify geochemical facies, groundwater samples for major ions, stable isotopes and some municipal tracers were collected from 35 wells in an established network of monitor wells. Wells were purged with a bailer or 12V pump and EC, …

Enrichments Of Heavy Sulfur (34s) In Sulfide Minerals: Gas Hydrates, Methane Delivery, And Anaerobic Methane Oxidation, Walter S. Borowski, Namcy M. Rodriguez, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

The sulfur isotopic composition of authigenic, sedimentary sulfide minerals is largely controlled by sulfate reduction and related processes within sedimentary environments. Histograms show that that d³⁴S values of sulfide minerals forming in depositional and diagenetic environments are most often negative (d³⁴S < 0^o/_oo CDT) reflecting the original isotopic composition of seawater sulfate (now ~21^o/_oo), microbially-mediated fractionations of ~-8 to -40^o/_oo (a = 1.029-1.059) during sulfate reduction, and more extreme fractionations caused by sulfur disproportionation. Enrichments of heavy sulfur (d³⁴S > 0^o/_oo) in sulfide …

A Novel Pervious Cement Reaction Barrier (Pcrb) In Situ Arsenic Remediation System, Morgan Liane Jones

Masters Theses & Specialist Projects

No abstract provided.

Geochemical And Geochronological Constraints On The Tectonothermal History Of The Central And Eastern Nepal Himalaya: Implications For Thermal-Mechanical Models, Stacey Lynn Corrie

Boise State University Theses and Dissertations

Syntheses of Himalayan tectonics imply an average shortening rate of ~2 cm/yr across the Himalaya over the last 20-25 Myr. However, despite decades of research, basic questions still remain about how strain was partitioned. Fluctuations in the timing and rate of thrusting could have significant implications for strain partitioning across the Himalaya, and for partitioning during collisional orogenesis as a whole.

Due to the observed chronology and thermobarometry of Greater Himalayan Sequence (GHS) rock units in the Annapurna region of central Nepal, we revise the original interpretation of the Bhanuwa Fault from a normal fault to a thrust, and identify …