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Full-Text Articles in Geology

Preliminary Assessment For Critical Minerals In The Terlingua Quicksilver District, Texas And Tres Marias Mine, Chihuahua, Mexico, Eduardo Lee Zuniga Dec 2023

Preliminary Assessment For Critical Minerals In The Terlingua Quicksilver District, Texas And Tres Marias Mine, Chihuahua, Mexico, Eduardo Lee Zuniga

Open Access Theses & Dissertations

The Terlingua Quicksilver district was discovered around the 1880s and was a mercury producing district from 1900 through 1946. The most productive years were during World War one and two. From 1900-1946 the Terlingua Quicksilver District (TQD) produced 150,000 flasks; 80% came from three mines: the Rainbow-Chisos, Mariposa, and Study Butte mines. The structural controls of the Mercury mineralization within these mines are breccia pipes and fractures, often located near igneous intrusions. This study will assess the potential for Critical Minerals and Rare Earth Elements in the Terlingua Quicksilver District. Fifty-five samples have been collected and analyzed for forty-four different …


Uranium Series Dating And Geochemistry Of Fault Zone Precipitated Secondary Carbonates: Insights Into Paleo Fluid Sources, Tectonics And Climate In The Rio Grande Rift, Victor Higareda Garcia Jan 2020

Uranium Series Dating And Geochemistry Of Fault Zone Precipitated Secondary Carbonates: Insights Into Paleo Fluid Sources, Tectonics And Climate In The Rio Grande Rift, Victor Higareda Garcia

Open Access Theses & Dissertations

Fault zones in the shallow crust impact a variety of geological processes including mineral deposition, fluid flow patterns in shallow and deep groundwater aquifers, and most importantly seismic activity. The specific interplays of fault zones, seismicity, and groundwater flows are complex and not well understood despite the importance they have to society. The Rio Grande rift is a region impacted by seismic and volcanic activity that place the first order control on mineral formation and fluid flow patterns. It is also a region that is often disregarded as a seismic hazard due to its inferred low tectonic rates and long …


Precipitation And Transformation Of Iron-Sulfide Nanoparticles In Low-Temperature Aqueous Environment: Effects Of Reactant Iron And Sulfide Sources, Ezequiel A. Moreno Flores Jan 2019

Precipitation And Transformation Of Iron-Sulfide Nanoparticles In Low-Temperature Aqueous Environment: Effects Of Reactant Iron And Sulfide Sources, Ezequiel A. Moreno Flores

Open Access Theses & Dissertations

Iron sulfide nanoparticles assume an important role within a wide range of geological settings as indicators of redox environmental conditions and elemental cycling mechanisms. Initial precipitates of iron sulfide are exclusively nanoscale sized in low temperature aqueous conditions and have been reported to go through diverse morphological and phase transformations, possibly leading to the ultimate deposits of pyrite in geologic records of various times. A systematic understanding of how the early-stage nanoparticles of iron sulfide may develop into more crystalline iron sulfide forms is still lacking however. The major goal for this study was to illuminate the effects of the …


Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia Jan 2019

Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia

Open Access Theses & Dissertations

This study provides new insights into the geometry and timing of ductile, syn-metamorphic structures in the central Panamint Mountains of eastern California. The study focused on Surprise Canyon, where exposures of Meso- to Neoproterozoic miogeocline rocks, reworked crystalline basement, and syn-metamorphic granitoids record fabric overprints indicative of at least two distinct dynamo-thermal metamorphic events. Prograde metamorphism at greenschist and amphibolite metamorphic facies conditions occurred during Early Jurassic plutonism based on deformation of a dioritic pluton with a U-Pb date reported here of 175.6 ± 3.2 Ma. Mid Jurassic deformation (D1) generated the main continuous cleavage in the rocks (S1) as …


Trace Metal And Metalloid Behavior In The Submicron Scale Components Of Coal Fly Ashes: Insights From Combined Microscopic And Microbiological Studies, Matthew Costa Jan 2018

Trace Metal And Metalloid Behavior In The Submicron Scale Components Of Coal Fly Ashes: Insights From Combined Microscopic And Microbiological Studies, Matthew Costa

Open Access Theses & Dissertations

For over a century, coal has been used worldwide to meet ever-growing energy demands. Coal combustion accounts for over 30% of electricity generation in the United States. In the U.S., coal combustion produces annually over 100 million tons of coal combustion products (CCPs) of which only 30% are used in beneficial and economic ways. One of the primary CCPs from coal-burning power plants is fly ash, typically fine-sized and enriched in many trace elements (e.g., arsenic, chromium, lead, and vanadium). When disposed in the environment, fly ash may release significant concentrations of trace elements into surrounding ecosystems and induce toxicity …


Gypsum, Calcite, And Dolomite Caprock Fabrics And Geochemistry From The Gypsum Valley Salt Diapir, Paradox Basin, Southwestern Colorado, Kevin Lerer Jan 2017

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 …


Genesis Of Unique Carbonate Fans In A Pre-Salt Reservoir Analogue, Indio Mountains, West Texas, Andre Llanos Jan 2017

Genesis Of Unique Carbonate Fans In A Pre-Salt Reservoir Analogue, Indio Mountains, West Texas, Andre Llanos

Open Access Theses & Dissertations

Hydrocarbon exploration in pre-salt sediments of rift basins on the South Atlantic Margin have proven to be successful major oil plays. Located on the western margin of the rift, the Brazilian pre-salt reservoirs of the Santos, Campos, and Espirito Santo Basins are hosted by lacustrine/marine-influenced carbonates that comprise laterally extensive, laminated microbialite facies. The Indio Mountains, located in West Texas, provide well-exposed outcrops of Lower Cretaceous marine and non-marine rift basin strata that can be considered a reservoir-analog to the South Atlantic Margin pre-salt facies. Of particular interest for hydrocarbon exploration are unique carbonate features that have been discovered in …


Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea Jan 2017

Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea

Open Access Theses & Dissertations

Dry deposition significantly affects evolution of the critical zone by nutrient supply and contributing to soil genesis. Dust influx and cycling in soils are difficult to quantify because dust sources can be chemically similar to local soils. White Sands, New Mexico, emits gypsum dust with a unique chemical and isotopic signature, providing an opportunity to investigate dust deposition and its movement in soils. This study evaluated the mobility of White Sands dust particles in the critical zone at White Mountain, New Mexico, a highland 100 km downwind. Four soil profiles were collected over limestone, igneous, mixed limestone and dolostone, and …


Geochemical Signatures As A Chemostratigraphic Tool To Correlate Stacked Carbonates Of The Glorieta, Victorio Peak, Cutoff, And Upper San Andres Formations West Dog Canyon, Guadalupe Mountains, New Mexico, Eric Bergersen Jan 2016

Geochemical Signatures As A Chemostratigraphic Tool To Correlate Stacked Carbonates Of The Glorieta, Victorio Peak, Cutoff, And Upper San Andres Formations West Dog Canyon, Guadalupe Mountains, New Mexico, Eric Bergersen

Open Access Theses & Dissertations

For oil exploration, stratigraphic correlation of formations over distance and across structural complications is essential. I tested if an established method – carbon and oxygen isotope composition of carbonates (δ 18Ocarbonate, δ13Ccarbonate) and a new chemostratigraphic tool – sulfur isotope composition of Carbonate Associated Sulfate (δ34SCAS) can aid in the correlation of rock packages belonging to multiple stacked carbonate horizons from a carbonate platform.

In my study area, located in the Brokeoff Mountains, north of the Guadalupe Mountains National Park, the δ18Ocarbonate, δ 13Ccarbonate and δ34SCAS scatter strongly within single beds of the Leonardian-aged Victorio Peak Formation. In stratigraphic order, …


Geology, Geochemistry, And 3d Geological Modelling Of The Independencia - Los Bancos Ag-Au Epithermal Vein Systems In The Palmarejo District, Chihuahua, Mexico, Arturo Ramirez Jan 2016

Geology, Geochemistry, And 3d Geological Modelling Of The Independencia - Los Bancos Ag-Au Epithermal Vein Systems In The Palmarejo District, Chihuahua, Mexico, Arturo Ramirez

Open Access Theses & Dissertations

The Sierra Madre Occidental (SMO) is a Cretaceous-Tertiary silicic ignimbrite province in northwestern Mexico. It is the result of tectonic and magmatic events produced by the subduction of the Farallon plate under North America (80-40 Ma) and the opening of the Gulf of California (14-12 Ma), thus forming the SMO metallogenic provinces. The Late Eocene to Oligocene was a major period of metallic mineralization hosting various deposit types, principally Ag-Au (±Pb-Zn-Cu) epithermal veins, which have been economically significant.

The study area lies in the Palmarejo district, operated by Coeur Mining Inc., which was the worldâ??s fifth largest silver producer in …


National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray Jan 2016

National Evaluation For Development And Exploration Potential Of Mineral Commodities In Produced Waters, Stephanie Ray

Open Access Theses & Dissertations

The U.S. Geological Survey recently updated a geochemical database consisting of data for approximately 160,000 produced waters samples, primarily from petroleum and geothermal reservoirs. Using major and trace elements from conventional and unconventional well types from the database, this Thesis provides a comprehensive, national evaluation for mineral commodity potential in produced waters. Produced waters contain virtually every naturally occurring element and can range in salinity to several times that of seawater. Despite the typical outlook to view produced waters as a waste, they have potential for natural resource development.

This Thesis provides, for each mineral commodity found in the produced …


Regional Geochemical Mapping Of The Superior Upland Province; Ichnology Of The Cretaceous Mesilla Valley Formation, Cerro De Cristo Rey; A New Ichnospecies Of Cardioichnus From The Cretaceous (Albian) Of New Mexico; A Pedagogy For The Cerro De Cristo Rey Tracksite; Walking In The Footprints Of Dino, Eric J. Kappus Jan 2016

Regional Geochemical Mapping Of The Superior Upland Province; Ichnology Of The Cretaceous Mesilla Valley Formation, Cerro De Cristo Rey; A New Ichnospecies Of Cardioichnus From The Cretaceous (Albian) Of New Mexico; A Pedagogy For The Cerro De Cristo Rey Tracksite; Walking In The Footprints Of Dino, Eric J. Kappus

Open Access Theses & Dissertations

This is a multi-disciplinary study that covers a variety of geoscience topics on both international borders of the continental United States. This Dissertation is the product of several separate investigations. First is a report on the landscape geochemistry of the Superior Upland Province of Minnesota, Wisconsin, and Michigan, with regional maps of 37 chemical elements interpreted in terms of bedrock, glacial reworking, and anthropogenic influence. The next 2 sections are reports on the invertebrate ichnology of the Cretaceous Mesilla Valley Formation at Cerro de Cristo Rey, including the proposal of a new ichnospecies of echinoid resting trace, Cardioichnus biloba nov. …


Trace Element Behavior During Coal Combustion: Insights From Cadmium And Zinc Isotope Analysis, Fotios Fouskas Jan 2015

Trace Element Behavior During Coal Combustion: Insights From Cadmium And Zinc Isotope Analysis, Fotios Fouskas

Open Access Theses & Dissertations

Due to its low cost and abundance, coal has been pervasively used in recent decades to meet large energy demands worldwide. Coal combustion provides the dominant electrical source in the U.S and produces over 100 million tons of coal combustion products (CCPs) per year domestically. The disposal/beneficial use of CCPs has the potential to release toxic trace elements, including cadmium (Cd) and zinc (Zn), into the environment. High temperature combustion of coal changes both physical states and chemical properties of Cd and Zn compounds in CCPs. Related processes such as evaporation and condensation, can lead to mass-dependent fractionation of Cd …


Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez Jan 2013

Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez

Open Access Theses & Dissertations

No abstract provided.


In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar Jan 2013

In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar

Open Access Theses & Dissertations

Zircon data from South Karakoram gneiss dome provide evidence for Proterozoic inherited cores (1.8-1.9 Ga and 2.3-.2.5 Ga) surrounded by migmatitic overgrowth with ages ranging from ~6 to ~20Ma. Oxygen isotopic data of Neogene migmatite and inherited core is similar and indistinguishable ranging from 7.5 to 9.5 /. However, Neogene overgrowth is significantly less evolved than the inherited core in terms of Hf composition. This implies that the Hf composition of the migmatitic zircons is not controlled exclusively by the dissolution of the inherited cores and that contamination by external melts is likely. Isotopic data from the Baltoro plutonic unit …


Isotope Geochemistry And Geochronology Of Lavas From The Line Islands Chain, Central Pacific Basin: Insight Into The Origin Of The Line Islands, Lauren Storm Jan 2012

Isotope Geochemistry And Geochronology Of Lavas From The Line Islands Chain, Central Pacific Basin: Insight Into The Origin Of The Line Islands, Lauren Storm

Open Access Theses & Dissertations

Geochemical compositions of melts produced in the Earth's mantle provide key data for understanding Earth's internal structure. Particularly, the compositions of unusually large outpourings of basaltic lavas in large igneous provinces involve substantial source volumes, thereby contributing to our understanding of mantle structure and dynamics. Although the origin of such lavas remains enigmatic, geochemically they may originate from Earth's oldest and deepest mantle reservoir, transported by a mantle plume or by entrainment in passive upwelling beneath a fast spreading center. The Pacific Ocean basin hosts several large igneous provinces that formed near a triple junction of three oceanic plates, and …


Dispersion Geochemistry At Different Scales At The Nopal I Deposit, Peña Blanca Uranium District, Chihuahua, Mexico, Katrina Pekar-Carpenter Jan 2011

Dispersion Geochemistry At Different Scales At The Nopal I Deposit, Peña Blanca Uranium District, Chihuahua, Mexico, Katrina Pekar-Carpenter

Open Access Theses & Dissertations

The Nopal I mine in the Peña Blanca Uranium District, Chihuahua, Mexico is a natural analog for the geologic storage of nuclear waste. This dissertation presents data from two sites within Nopal I: 1) the PB-1 core, which was drilled along the extent of uranium mineralization in the Nopal I mine; and 2) a high-grade stockpile boulder from the mineralized Nopal tuff.

The PB-1 core allowed an investigation into the mineralogical and geochemical changes that are important to research on a nuclear waste repository. Five zones were determined to control these changes: 1) Zone 1, the primary uranium mineralization (quartz-uraninite-pyrite-kaolinite-ilmenite); …


Mineralization In The San Juan Mountains, Colorado, William M. Sheriff Jan 2010

Mineralization In The San Juan Mountains, Colorado, William M. Sheriff

Open Access Theses & Dissertations

none


Application Of Copper And Zinc Isotopes To Fingerprint Metal Sources And Identify Attenuation Mechanisms In The Abandoned Waldorf Mine Area, Clear Creek County, Colorado, Suzan Aranda Luna Jan 2010

Application Of Copper And Zinc Isotopes To Fingerprint Metal Sources And Identify Attenuation Mechanisms In The Abandoned Waldorf Mine Area, Clear Creek County, Colorado, Suzan Aranda Luna

Open Access Theses & Dissertations

Acid rock drainage (ARD) is caused by the oxidative weathering of sulfide minerals. Sulfur is oxidized by dissolved oxygen or Fe(III) and sulfate ions, metals, and protons are released into the environment. Hence, the pH of nearby water and soils often decreases in response to ARD while metal concentrations increase. Because a large part of the Rocky Mountains of Colorado are highly mineralized (i.e., the Colorado Mineral Belt), ARD is a serious problem in this region. Moreover, the many abandoned mining areas in the Rocky Mountains that include waste rock piles, tailings impoundments, and surface disturbances add to the problem …


Suswa Volcano, Kenya Rift: Evidence Of Magma Mixing, Na-F Complexing And Eruptions Triggered By Recharge, Vanessa Veronica Espejel Garcia Jan 2009

Suswa Volcano, Kenya Rift: Evidence Of Magma Mixing, Na-F Complexing And Eruptions Triggered By Recharge, Vanessa Veronica Espejel Garcia

Open Access Theses & Dissertations

The Cenozoic East African rift system (EARS) is a sequence of grabens, intraplate transforms, accommodation zones, and abundant magmatism. The Central Kenya Peralkaline Province (CKPP) includes a variety of volcanic rocks -trachyte, pantellerite, comendite, phonolite, trachy-basalt, basaltic trachy-andesite, and basalt- which erupted from volcanoes including: Mount Kenya; Eburru and the Greater Olkaria volcanic complexes; Longonot, Menengai, and Suswa volcanoes; and Ndabibi, Elmenteita, and Tandamara mafic volcanic fields. Only two of the volcanoes, Mount Kenya (on the flank of the central graben) and Suswa (the southernmost of the CKPP volcanoes), have phonolites as part of their assemblage.

The evolution of Suswa …


Zinc And Copper Isotopes As Tracers Of Anthropogenic Contamination In A Sediment Core From An Urban Lake, Anita Thapalia Jan 2009

Zinc And Copper Isotopes As Tracers Of Anthropogenic Contamination In A Sediment Core From An Urban Lake, Anita Thapalia

Open Access Theses & Dissertations

Concentration data alone are often insufficient to resolve metal sources. This study applies stable Zn and Cu isotopes to fingerprint and track the sources of these metals in a sediment core from Lake Ballinger near Seattle, Washington, USA. The base of the Lake Ballinger core pre-dates settlement in the region, while the upper sections record the impact of atmospheric emissions from the nearby Tacoma smelter, as well as Cu and Zn inputs from urban sources. δ66Zn and δ65Cu varied by 0.42 / and 0.29 /, respectively, over the >300 year core record. Isotopic changes were correlated …


A Multi-Tracer Study Of Saltwater Origin, Cross-Formational Flow, And The Geochemical Evolution Of Groundwater In The Southern High Plains Aquifer Along The Western Caprock Escarpment, East-Central New Mexico, Jeff Langman Jan 2008

A Multi-Tracer Study Of Saltwater Origin, Cross-Formational Flow, And The Geochemical Evolution Of Groundwater In The Southern High Plains Aquifer Along The Western Caprock Escarpment, East-Central New Mexico, Jeff Langman

Open Access Theses & Dissertations

Sustainable management of groundwater resources requires sufficient knowledge of the distribution of fresh and saline groundwater and the processes affecting saltwater intrusion that may influence the beneficial use of groundwater. A hydrogeologic investigation that coupled various chemical and isotopic tracers, including 3H/3He, 14C, δD, δ18O, 87Sr/86Sr, and δ11B, with the physical characteristics of the aquifer was conducted to determine source waters, the origin of saltwater and its influence through cross-formational flow, and water-rock interactions in the Southern High Plains aquifer along the Western Caprock Escarpment. Sub-aquifers or local flow systems are present along the Western Caprock Escarpment, and the study …