Geology Commons^™

Mgrre_Thinsections_Mgrre-129_12, Mgrre

Thin Sections

No abstract provided.

Mgrre_Thinsections_Mgrre-129_8, Mgrre

Thin Sections

No abstract provided.

Phosphate Mineralogy And Paragenesis Of The Fletcher Pegmatite, North Groton, New Hampshire, Susanna T. Kreinik

LSU New Orleans Theses and Dissertations

Investigation of phosphate assemblages selectively collected at the Fletcher Mine pegmatite, North Groton, New Hampshire, yielded eighteen discrete secondary phosphate species. Secondary phases were formed via metasomatic (high temperature) and hydrothermal (low temperature) alteration of primary triphylite and fluorapatite. Mineral associations bear proximal phases known to occur under contrasting conditions, both oxidizing and reducing, suggesting the formation of microenvironments during concomitant mineral generation. Late-stage hydrothermal fluids provide ions taken up in low temperature secondary phases with calcium and magnesium most prevalent in these suites. High iron to manganese ratios in analyzed specimens establish the relative evolution of the pegmatite host. …

Remote Sensing Application For Landslide Detection: Monitoring Along Eastern Lake Michigan (Miami Park, Mi), Guzalay Sataer

Dissertations

I assessed the nature and spatial and temporal patterns of deformation over the Miami Park bluffs on the eastern margin of Lake Michigan and investigated the factors controlling its observed deformation. Our approach involved the following steps: (1) extracting bluff deformation rates (velocities along the line of sight of the satellite) using a stack of Sentinel-1A radar imagery in ascending acquisition geometry acquired between 2017 and 2021 and applying the Intermittent Small Baseline Subset (ISBAS) InSAR time series analysis method; (2) generating high-resolution (5 cm) elevation models and orthophotos from temporal unmanned aerial vehicle (UAV) surveys acquired in 2017, 2019, …

Applications Of Micro-X-Ray Fluorescence (Μxrf) Techniques To Ore Formation Questions In Economic Geology, Hannah Adwoa Buamono

Open Access Theses & Dissertations

Advances in x-ray optics over the past decade have enabled a new generation of benchtop micro energy-dispersive x-ray fluorescence (µXRF/EDS) instruments to analyze samples with an x-ray spot size of 25 microns or less and detection limits of tens to hundreds of parts per million. The analysis of samples from mineral (ore) deposits may illustrate some of the capabilities and limitations of these instruments applied to geoscience problems. The qualitative elemental analysis process allows the production of detailed elemental maps which, together with line scan profiles and other petrographic and geochemical evidence, leads to a better definition of key chemical, …

Mgrre_Thinsections_Mgrre-129_6, Mgrre

Thin Sections

No abstract provided.

Mgrre_Thinsections_Mgrre-129_2, Mgrre

Thin Sections

No abstract provided.

Mgrre_Thinsections_Mgrre-129_5, Mgrre

Thin Sections

No abstract provided.

Mgrre_Thinsections_Mgrre-129_7, Mgrre

Thin Sections

No abstract provided.

Hydrothermal Alteration Targeting And Geophysical Mineral Exploration Of Eureka And Sylvanite Mining Districts, Southwest New Mexico, Kenneth Singh

Open Access Theses & Dissertations

As part of the southwestern North American porphyry copper province, mining of natural resources in New Mexico has historically played a crucial role in economic development for over 150 years including this project area in the Little Hatchet Mountains. The northern half of the Little Hatchet Mountains lies in Grant County and includes the Eureka Mining District (EMD) whereas the southern half is in Hidalgo County and includes the Sylvanite Mining District (SMD), 38 miles southeast of Lordsburg. The EMD, a copper and silver-lead mining district from 1880-1961, had a total estimated production from the Laramide veins of 2.9 million …

Using Ground Penetrating Radar To Investigate Controls On Pedogenic Calcium Carbonate Distribution In Dryland Critical Zones, Nohemi Valenzuela Garay

Open Access Theses & Dissertations

Caliche or pedogenic calcium carbonate (CaCO3) layers are a common feature of arid soils, but the environmental controls on their distribution are not fully understood. Caliche layers are thought to play an important role in shallow subsurface water storage and movement, due to their water retention capacity and ability to impede vertical water transport (Hennessy et al., 1983). Therefore, caliche distribution and stability play a role in controlling water distribution in arid lands. However, due to its largely subsurface nature, caliche can be difficult to investigate and map without significant effort. I hypothesize that noninvasive geophysical methods, such as ground-penetrating …

Orbital Mapping Of Seasonal And Yearly Changes In Co2 And Water Ice On The Southern Polar Cap Of Mars, Victoria Michell Ann Karnes

Graduate Theses and Dissertations

This research exhibits a new foundation for the rates of change in CO2 and water ice on the southern polar cap of Mars, where the annual precipitation cycles are known to fluctuate seasonally between the north and south pole, based on observations from the Compact Reconnaissance Imaging Spectrometer (CRISM). The conventional belief is that both CO2 ice and water ice on the southern polar cap condenses and evaporates over the course of a Martian year (MY), condensing during the Martian spring and summer and evaporating during the Martian fall and winter. With this theory in mind, CO2 and water ice …

Trace Element Behaviors During Igneous Evolution And Hydrothermal Alteration Of An Evolved Rhyolite, The Blawn Formation, Wah Wah Mountains, Utah: Implications For Critical Metal Abundances In Highly Evolved Rhyolites, Drew William Barkoff

UNLV Theses, Dissertations, Professional Papers, and Capstones

A-type rhyolites and granites often contain elevated concentrations of the rare earth elements (REE) and many other critical trace elements relative to I- and S-type rhyolites and granites. Their trace element-enriched nature makes them potentially prospective bulk tonnage, low-grade resources of the REE and many other critical trace elements, including Li, Be, Mo, Sn, and W, but little work has been performed to delineate their economic potential. The 22.1 Ma Red Beryl Rhyolite (RBR) and the 18.3 Ma Tetons Rhyolite (TR) units of the Blawn Formation represent two A-type rhyolite domes located in the southern Wah Wah Mountains of Utah. …

Paleoenvironmental Changes Across The Devonian-Carboniferous Transition, Audrey M. Warren

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Devonian-Carboniferous (D-C) transition was a critical interval in earth history, witnessing profound environmental changes associated with plant and animal evolution and extinction. Two first-order mass extinctions occurred leading up to the D-C boundary: the Kellwasser Event at the Frasnian-Famennian (F-F) boundary (~371 Ma) and the D-C boundary Hangenberg Event (~359 Ma). Both events were associated with significant sea level changes and major carbon cycle perturbations, evidenced by widespread deposition of black shale and positive carbon isotope (δ13C) excursions, all of which have been used to correlate these events across the globe. Because preservation of black shale requires anoxic conditions, …

Pleistocene Deposits Of Lower Wahweap Creek And Its Tributaries, Southern Utah, Noah Slade

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The famous landscapes of the Colorado Plateau have been created over millions of years, primarily by erosive forces of wind and water. Interruptions in the long-term erosion of the landscape occur when streams gain more sediment than they can transport, which causes deposition along channels and floodplains. The resulting sequences of terrace deposits are used by geologists to study when and how river systems have evolved.

Mammoth bones were recently discovered in stream deposits along Wahweap Creek, a tributary of the Colorado River in southern Utah. Previous work indicates that the deposits pre-date the last ice age, making it one …

Late Pleistocene Piedmont Records In The Grand Staircase Region, Southern Utah, Alexander K. Short

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Today the climate in the southwestern United States is arid, characterized by desert landscapes and habitats, periods of drought, and arroyo streams that frequently fill with, and erode, through fine riverbed sediments. A series of cliffs and benches rising from the Grand Canyon to the southern plateaus of Utah, known as the Grand Staircase - home to Kodachrome Basin State Park, Bryce Canyon, are a classical example of this environment as we know it today. However, a record spanning the past 300 thousand years is preserved on the steps of the staircase indicating periods in the past where the climate …

Bedrock Geology Map Of The Naomi Peak 7.5' Quadangle, Cache County, Utah And Novel Age Constraints On Its Cambrian Strata, Hannah R. Cothren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geologists use various “rock-clocks” in order to interpret the timing and tempo of events in Earth’s history. These include global geochemical events in the oceans (chemostratigraphy), the evolution of certain fossil species (trilobite biostratigraphy), and the radiogenic decay of uranium to lead in certain mineral such as zircon (U-Pb geochronology). Integrating these methods in the stratigraphic record in one location can provide a well-constrained timeline for a select part of the Geologic, or Deep Time, record. This technique is especially important in the Cambrian Period (538.8 to 486.9 million years; Ma), which sets the stage for life today with the …

Age And Genesis Of W-Mo-Cu Mineralization, Gold Hill, Utah, Nathan J. Carey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Utah's Gold Hill mining district hosts a Jurassic felsic pluton (~80 km^2) that was emplaced into a Mississippian to Pennsylvanian carbonate-dominated sedimentary sequence and is spatially associated with numerous polymetallic mineral deposits. This study focuses on W-Mo-Cu mineralization at the Lucy L., Doctor, Yellow Hammer, Reaper, and Rustler deposits within the district. The new, detailed petrographic observations, mineral chemistry (on scheelite, molybdenite, chalcopyrite, magnetite, garnet, and pyroxene), and Re-Os molybdenite geochronological data presented here allows for the determination of key mineral associations and paragenesis, the characterization of deposit types and their evolution, and the constraining of the relative and absolute …

Hydrogeologic Heterogeneity Identification: Using Inverse Modeling Of Synthetic Borehole Temperatures To Predict Groundwater Flux, Kevin Heintz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Heat has been effectively used as a groundwater tracer for decades, and high-resolution temperature data can better identify and quantify discrete flow zones. Refinements to the numerical modeling of advective heat transfer in borehole temperature sensing deployments can improve understanding of dynamic hydrogeologic systems. In my thesis, I develop a novel two-dimensional coupled radial groundwater flow and heat transfer numerical model that considers intra-borehole vertical flow. To test the performance of this model, I used finite element analysis to generate synthetic data sets consisting of prescribed variable flow fields and resulting borehole temperatures. I input synthetic temperatures into the two-dimensional …

Along Strike Tectonic Evolution Of The Neogene Bermejo Foreland Basin And Eastern Precordillera Thrust Front, Argentina (30-32ºs), Zoey Catherine Plonka

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Bermejo retroarc foreland basin system formed in flexural response to Miocene crustal thickening in the Andean orogenic system, specifically, the eastward propagation of the Precordillera fold-thrust belt and the basement-involved uplift of the Sierras Pampeanas. Previous work in the area has mainly focused on the mechanisms and expression of flat slab subduction and the structural geometry of the basement-involved Sierras Pampeanas and east-vergent Precordillera fold-thrust belt at depth. Much of this work has furthered the understanding of Bermejo basin evolution north of 31ºS, however debate still exists whether the N-S trending Bermejo basin evolved synchronously or asynchronously through time. …