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Mechanisms Of Gold Enrichment In Seafloor Massive Sulfide Deposits: A Study On The Higashi-Aogashima Hydrothermal Field, Claudia Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The study of Seafloor Massive Sulfides (SMS) deposit formation is vital for assessing both the economic potential and environmental risks posed by future marine mining projects. Metal-rich SMS deposits form in hydrothermal vent systems within tectonically active regions, such as back-arc basins, where faults enhance crustal permeability, enabling fluid migration driven by magmatic heat sources at depth in the crust. Currently our understanding of SMS formation processes is based on bulk-rock geochemical and isotopic data, lacking the necessary spatial and temporal resolution to understand ore forming processes. As a result, critical gaps remain in understanding the exact mechanisms responsible for …

The Application Of Detrital Zircon Geochronology, Pressure-Temperature Modeling, Monazite Petrochronology, And Quartz-In-Garnet Elastic Geobarometry To The Tectonic Evolution Of The Funeral Mountains And Related Metamorphic Core Complexes, Suzanne Renae Mulligan

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation investigates and applies different techniques for studying mid-crustal metamorphic rocks including detrital zircon geochronology, monazite petrochronology, thermodynamic pressure-temperature modeling, and elastic geobarometry. The first chapter reconstructs stratigraphy in deformed metamorphic rocks from the Funeral Mountains metamorphic core complex in Death Valley, California, and the Bullfrog Hills, Nevada, using U-Pb detrital zircon (DZ) geochronology. This study documents another successful application of stratigraphic techniques applied to metamorphic rocks and migmatites. DZ geochronology identified Pahrump Group metasediments in rocks that were previously interpreted to be Paleoproterozoic basement gneisses, providing insights into the distribution of Rodinia rift basins. This analysis has shown …

Initial Measurements On The Effect Of Stress On P- And S-Wave Velocities In Olivine, Taryn Traylor

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is well known that elasticity is a key physical property in the determination of the structure and composition of the Earth and provides critical information for the interpretation of seismic data. This study investigates the stress-induced variation in elastic wave velocities, known as the acoustoelastic effect, in San Carlos olivine. A recently developed experimental ultrasonic acoustic system, the Directly Integrated Acoustic System Combined with Pressure Experiments (DIASCoPE), was used with the D-DIA multi-anvil apparatus to transmit ultrasonic sound waves and collect the reflections. We use the DIASCoPE to obtain longitudinal (P) and shear (S) elastic wave velocities from the …

Structural Evolution And Regional Implications Of The Arrowhead Mine Fault Within The Pahranagat Shear Zone, Nevada, Usa, Michael Dennis Evans

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Basin and Range province is characterized by normal faults associated with

extension, but the occurrence of strike-slip faults and the seismic hazard accompanying

them is less understood. One major strike-slip zone, the Pahranagat shear zone (PSZ),

lies in Lincoln County, Nevada and within the boundary zone between northern Basin

and Range (NBR) and central Basin and Range (CBR) sub-provinces. The PSZ is a 20-

25 km long zone of Cenozoic left-lateral faults. The Arrowhead Mine Fault (AMF) is one

of the three major faults in the PSZ. The western AMF and the faults that surround and

abut it are …

Perchlorate Bioremediation: Controlling Media Loss In Ex-Situ Fluidized Bed Reactors And In-Situ Biological Reduction By Slow-Release Electron Donor, Sichu Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

The main concern of perchlorate exposure through drinking water is its effects on the production of thyroid hormone, which is important for human metabolism and child’s brain development. The US Environmental Protection Agency (EPA) has listed perchlorate in the contaminant list as well as in the Unregulated Contaminant Monitoring rule.

The extent of perchlorate contamination can be categorized by the level of contamination into parts per million (ppm) levels, typically in locations where perchlorate was manufactured, and parts per billion (ppb) levels where perchlorate was used for various purposes. Ion-exchange is generally adopted for treating ppb levels of perchlorate while …

Porphyry Copper Exploration Of The Hualapai Mountains, Mohave County, Arizona, Usa: A Multi-Faceted Approach, Patrick Kevin Meazell

UNLV Theses, Dissertations, Professional Papers, and Capstones

A variety of exploration methods including geologic mapping, trace- and major-level geochemical analyses, fluid inclusion petrography, remote sensing, and SWIR clay spectroscopy were used to investigate the potential for porphyry Cu-Mo mineralization at the Wikieup prospect, in the southern Hualapai Mountains of northwestern Arizona. Aspects of the Mineral Park mine were used as an analogue to guide exploration due to the proximity and similar geology of the area.

The Hualapai Mountains are a series of northwest-trending Precambrian gneisses, schists, granitoids and amphibolites that have been cut by younger intrusive rocks. Within the Wikieup study area, the intrusive rocks include aplite …

The Mayan Ice Cap: Glacial Geology And Paleoclimate Of The Northern Guatemalan Highlands, Alex Joseph Roy

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Sierra de los Cuchumatanes region of the northern Guatemalan highlands supported a large plateau ice cap with an area of -40 km2 along with a group of 5 cirque glaciers -1 to 2 km2 during the local last glacial maximum (LLGM). A comprehensive mapping reconstruction of the northern Guatemalan highlands is presented here, including glacial geology and an estimate of maximum ice limits from physical evidence and computer modeling. The glacial geologic map was produced via field mapping with global positioning system (GPS) surveying combined with aerial stereo photographic and topographic map analysis. This new field work on moraine …

Geology Of The Southern Reveille Range, Nye County, Nevada, Matthew Alan Mckelvey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Reveille Range in central Nevada provides a unique window into the mid-Miocene geology and volcanology of the central Great Basin during the "ignimbrite flare up." Although faulted along its margins, the interior of the range is relatively undeformed thus preserving volcanic centers. The Reveille Range contains three mid-Miocene caldera complexes. Previous studies have identified the Goblin Knobs caldera (25.6 Ma) in the central Reveille Range and the caldera of northern Reveille Range (25.3 Ma) to the north. These calderas are completely filled with intracaldera tuffs. This study has identified a younger third caldera located in the southern part of …

An Economic Analysis Of The Arsenic Standard On Nevada, Jill S. Dale

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2001, the arsenic standard for drinking water was lowered from 50 parts per billion to 10 parts per billion. The clean-up costs for Nevada are estimated at approximately 400 million dollars. The purpose of this project is to examine the economic impacts the State of Nevada will absorb as a result of the new regulation. Research of historical data will be the basis for the project. National data from the U.S. Environmental Protection Agency and data collected from the State of Nevada will be accompanied by comparable research data found through other sources

The Study Of Yucca Mountain For A Possible Nuclear Storage Facility Science Vs. Politics, Anna Leske

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this paper is to determine whether scientific or political methods were used by the of the United States Congress in the study of the nuclear waste storage facility in Yucca Mountain, Nevada. The history nuclear power and the history of the Johnston compromise that lead to the elimination of Texas and Washington States as possible sites for the repository is explained. A review of the conflicts between Nevada politicians and the U.S. Congress over the designation of Yucca Mountain as the sole study for a permanent storage site of the nation's high-level nuclear waste is addressed along …

The Sloan Sag: A Mid-Miocene Volcanotectonic Depression, North-Central Mccullough Mountains, Southern Nevada, Hayden L. Bridwell

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the Hidden Valley area of the north-central McCullough Mountains, southern Nevada, mid-Miocene andesite and dacite domes, flows and pyroclastic units (the Sloan volcanics) partially fill a sag in the underlying Hidden Valley volcanics. The 13.5 km diameter sag formed during and/or after the eruption of the Sloan volcanics. Sagging was accommodated by a combination of movement on the McCullough Wash fault system, and subsidence into evacuated chambers.

Major, trace and rare-earth element geochemistry suggests that the rocks of the Sloan volcanics belong to four groups, each of which were produced by partial melting of chemically distinct sources. With the …

Spring Flow In A Portion Of Grand Canyon National Park, Arizona, David Bruce Goings

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hermit, Monument, Salt, and Horn Creeks flow through four side canyons of the Colorado River within the Grand Canyon. They lie just west of Grand Canyon Village on the south side of the canyon. Each of these creeks is fed by at least one spring.

Comparisons of flow at each of these springs for a 14 month period, and precipitation on the south rim show a close correlation. The lag period between recharge at the rim and discharge at the springs is less than one month for Hermit Creek and between one and two months for the other three creeks. …