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Full-Text Articles in Physical Sciences and Mathematics

Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery Dec 2023

Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery

Earth and Planetary Sciences ETDs

The 1.2 Ma Valles Caldera in north-central New Mexico hosts a young igneous volcanic hydrothermal system after the model proposed in Goff and Janik (2000). The Sulphur Springs area within Valles Caldera is an acid-sulfate area typical of this model, discharging acidic waters (pH 1.5-3) formed by oxidation of magmatic H2S at the surface. We report on samples obtained from springs and streams collected between October 2021 and May 2023 in the Sulphur Creek and Alamo watersheds. Sulphur Creek receives input from Sulphur Springs and exhibits low pH (2-4) and high concentrations of Al (≤110 mg/L), Fe (≤60 …


Metagenomic Investigation Of Microbial Dark Carbon Fixation, Viral Interactions, And Horizonal Gene Transfer Within A Convergent Margin Subsurface Ecosystem, Timothy Joseph Rogers Aug 2023

Metagenomic Investigation Of Microbial Dark Carbon Fixation, Viral Interactions, And Horizonal Gene Transfer Within A Convergent Margin Subsurface Ecosystem, Timothy Joseph Rogers

Doctoral Dissertations

Convergent margins are geological regions where two or more tectonic plates collide, and the denser “subducting slab” is pushed beneath the less dense overriding plate. As the slab descends, it devolatilizes under higher temperatures and pressures, allowing dissolved inorganic carbon (DIC) and redox active volatile rich fluids to cycle between the upper crust and Earth’s mantle. These fluids migrate through cracks and fissures in the upper mantle and crust, fueling chemolithoautotrophy-based microbial ecosystems in the subsurface before they are expelled on the surface in the form of hydrothermal seeps and springs. Chemolithoautotrophic ecosystems, such as those in the Costa Rican …


Understanding The Connection Between Gypsum Blooms And Human Health At The Salton Sea, Isabel Ichiyama May 2023

Understanding The Connection Between Gypsum Blooms And Human Health At The Salton Sea, Isabel Ichiyama

Undergraduate Honors Theses

The Salton Sea is a closed hypersaline lake in Southern California that has been receiving little input over the past few decades, leading to desiccation that is rapidly increasing every year. This large-scale evaporation of the sea has led to increased dissolved solutes, high salinity, and gypsum blooms. Gypsum blooms, the precipitation of gypsum (CaSO42H2O) in the sea, have been a prominent facet of the sea and their distribution is well known. However, much of their chemistry and potential health hazards are still undetermined. Potential health effects from gypsum salt, an atmospheric dust particle present at the sea, have known …


Quantifying Heterogeneity Along A Hillslope Using Seismic Refraction, Structure From Motion, And X-Ray Fluorescence In The Piedmont, South Carolina, Leah Topping May 2023

Quantifying Heterogeneity Along A Hillslope Using Seismic Refraction, Structure From Motion, And X-Ray Fluorescence In The Piedmont, South Carolina, Leah Topping

All Theses

The critical zone (CZ) is the life sustaining outer layer of the earth that spans from the top of unweathered bedrock to the tops of the trees. This dynamic zone is always evolving because a variety of chemical, physical, and biological processes transform bedrock into regolith, creating a spatially heterogeneous CZ architecture. This study aims to investigate the relationships between regolith thickness, seismic velocities, and chemical profiles as a function of slope position and it is hypothesized bedrock composition, fracture density, and foliation are the key factors controlling the physical heterogeneity in the top 1-2 meters of the CZ. To …


Petrological And Geochemical Evaluation Of Rare-Earth Element Potential In The Sparta Granite Complex, Max J. Eshbaugh Jan 2023

Petrological And Geochemical Evaluation Of Rare-Earth Element Potential In The Sparta Granite Complex, Max J. Eshbaugh

Honors College Theses

Rare earth elements (REEs) are important resources with applications in the electronics, renewable energy, and automotive industries. REEs may be concentrated in the residual weathered portion of igneous parent rocks, typically granites. These residual deposits are mined in southeast Asia, but analogous climatic and geologic conditions suggest the existence of economically viable REE residual deposits in the southeastern United States (U.S.). The Sparta Granite Complex in east-central Georgia is a granitoid complex emplaced at the end of the Alleghanian orogeny, forming a suture between the Savannah River and Milledgeville terranes. Petrologic and geochemical assessments of the Sparta Granite and overlying …


Geology And Lithogeochemistry Of The Pickett Mountain Volcanogenic Massive Sulfide Deposit, Northern Maine, Michael J. Mccormick Aug 2021

Geology And Lithogeochemistry Of The Pickett Mountain Volcanogenic Massive Sulfide Deposit, Northern Maine, Michael J. Mccormick

Electronic Theses and Dissertations

The Pickett Mountain deposit is a volcanogenic massive sulfide (VMS) base-metal deposit located 15 miles north of Patten, ME. The deposit, discovered in 1979, was abandoned in 1989. The deposit remained abandoned until 2017, when Wolfden Mt. Chase LLC purchased the land for further development after Maine mining regulations changed. This project is a collaboration between the University of Maine, the University of Maine – Presque Isle, Wolfden Resources Corp., and the University of New Brunswick to better understand the regional and deposit-scale geology related to the deposit to fill in gaps of the geologic story of northern Maine as …


Analysis Of Water Concentration Formed Within Deformed Synthetic Quartz Crystals, Andrew Steward Jan 2021

Analysis Of Water Concentration Formed Within Deformed Synthetic Quartz Crystals, Andrew Steward

Williams Honors College, Honors Research Projects

Analyzing the strength of synthetic quartz is essential to understanding the strength of natural milky quartz, which likely controls the strength of Earth’s continental crust. Synthetic quartz is sometimes used for deformation experiments because it has a homogenous water distribution unlike natural milky quartz. The purpose of this study is to determine if annealing synthetic quartz at T = 600°C will convert the water in synthetic quartz to free water, like milky quartz, but with little water loss. Following two annealing experiments at Texas A&M University, I performed four annealing experiments to measure the water content of five synthetic quartz …


Petrogenesis And Tectonic Implications Of Cordierite-Orthoamphibole Gneisses (Cog) In The Nw Wyoming Province, Brianna K. Crenshaw Ms Jan 2021

Petrogenesis And Tectonic Implications Of Cordierite-Orthoamphibole Gneisses (Cog) In The Nw Wyoming Province, Brianna K. Crenshaw Ms

Graduate Student Theses, Dissertations, & Professional Papers

Studying cordierite orthoamphibole gneisses (COG) from five different mountain ranges across the Montana Metasedimentary Terrane (MMT) of the Wyoming Province offers a unique opportunity to elucidate the enigmatic origins and petrogenesis of the lithology in addition to gaining a further understanding of Precambrian crustal assembly processes. Geochemical analyses suggest that COG originates from a basalt that underwent metasomatic alteration, likely via seawater, prior to metamorphism. Moreover, COG is considered to represent oceanic crust that was part of the epicontinental sea adjacent to the Wyoming Province before collision with the Medicine Hat Block. Field observations of associated lithologies such as marbles, …


Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan Dec 2020

Surface Alteration In The Ölkelduháls, Nesjavellir, And Geysir Hydrothermal Systems, Iceland: Implications For Mars, Jordan Ludyan

Theses and Dissertations

Silica- and sulfate-rich deposits observed by Mars Exploration Rover (MER) Spirit near Home Plate, Gusev crater, Mars, indicate alteration of Mars basalt by a diverse array of hydrothermal fluids and processes. Constraining the precise fluid conditions present at the time of deposition for these deposits on Mars relies on investigations of terrestrial hydrothermal systems that produce similar mineral assemblages. Alteration products and fluids collected from the Ölkelduháls, Nesjavellir, and Geysir hydrothermal areas in southern Iceland cover a wide range of end-member and intermediate fluid and alteration environments, and provide a means to compare the secondary minerals produced from different hydrothermal …


Pumice Compositions And Mineral Chemistry From Lascar Volcano, Chile, Madelaine M. Stearn May 2020

Pumice Compositions And Mineral Chemistry From Lascar Volcano, Chile, Madelaine M. Stearn

MSU Graduate Theses

Lascar volcano is one the most active volcano in the Central Volcanic Zone of the Andean Cordillera, with 36 Holocene eruptions including a VEI 4 eruption in April 1993. Activity has not been consistent throughout time, and therefore, the processes behind it are poorly understood. Lascar volcano has cyclic behavior and has had four stages of activity, each of which had a unique eruptive style and product composition. Stage I (<43 >ka) had primarily mafic andesite lavas erupted effusively from a stratocone. Stage II initiated with dome building events ESE of the original vent and culminated in the 26.45 ka …


Geochemical Analysis And Heat-Treatment Of Natural Sapphires From Madagascar And Tanzania In Oxidizing And Reducing Conditions, Lukas Karuza, Dr. Michael B. Wolf, Brian Konecke Phd Jan 2020

Geochemical Analysis And Heat-Treatment Of Natural Sapphires From Madagascar And Tanzania In Oxidizing And Reducing Conditions, Lukas Karuza, Dr. Michael B. Wolf, Brian Konecke Phd

Geology: Student Scholarship & Creative Works

Natural or synthetic sapphires can be heat-treated to improve the clarity by removing “silk” (inclusions) and to change color by introducing color-inducing elements (i.e., chromophores) into the lattice structure or changing their valency. Due to these reasons, sapphires can be heat-treated to increase their monetary value. Twenty natural blue (C1), 20 green (C2), and 20 clear (C3) sapphires from Madagascar and Tanzania were heat-treated in a muffle furnace in oxidizing and reducing conditions, from 1200 to 1600℃, for 10-hour soak time. In total, 5 experiments were conducted in which soak time remained constant: experiment 1 was performed at 1200℃, exp. …


Geochemical Flux Analysis Of Glacial River Runoff For Sólheimajökull, Iceland, Jessica Garrison Jan 2020

Geochemical Flux Analysis Of Glacial River Runoff For Sólheimajökull, Iceland, Jessica Garrison

Mahurin Honors College Capstone Experience/Thesis Projects

Geochemical fluxes in aqueous studies are an essential component of research to understand weathering and changes in a hydrologic system. These data can indicate any discrepancies, outliers, or gradual changes in a water environment to gain information on pollutants, carbon cycles, biological input, etc. Glacial melt is the majority of the surface water present throughout the country. The melting amount is increasing with the temperatures, which can be monitored by the changes in geochemical flux during increased discharge in glacial rivers. A high-resolution data set of Sόlheimajökull Glacier in Iceland was used to determine how changing climatic conditions for the …


Development Of A Synthesis Method For O2-Releasing Compound For Microbiological Experiments, Danae Greco Jan 2020

Development Of A Synthesis Method For O2-Releasing Compound For Microbiological Experiments, Danae Greco

Williams Honors College, Honors Research Projects

Many celestial bodies within our solar system may have habitable environments due to the presence of liquid water. Europa, one of Jupiter’s moons, may be habitable because of its liquid ocean and other potentially biologically favorable conditions. The ocean on Europa is hypothesized to contain large amounts of oxidants and low pH due to the radiolytically processed icy ocean shell. This suspected environment on Europa is similar to the composition of acid mine drainage on Earth, which can house microbial communities in environments of extreme acidity. Similar chemical reactions in Europa’s ocean may occur to produce the appropriate reduction-oxidation gradients …


Geochemical Analysis Of The Chinchín Formation In Southern Ecuador, Katherine Ludwig May 2019

Geochemical Analysis Of The Chinchín Formation In Southern Ecuador, Katherine Ludwig

Celebration of Learning

The subduction of the Nazca Plate under the South American Plate has led to the uplift of the majority of the Andes Mountains, but in Ecuador, the Nazca Plate subducts underneath the North Andes Plate, which then collides with the South American Plate. This tectonic setting has formed two parallel mountain chains as well as a complex series of basins between them. However, the formations that make up these basins are poorly understood. This study focuses on the Chinchín Formation, an ~3.5 km thick, volcanic formation that serves as the bedrock of the Quingeo Basin in southern Ecuador. This study …


Magnetic Exploration Of The Crescent Formation, Washington: The Search For A Hidden Fault Near Dusk Point, Samuel G. Furmanski Jan 2019

Magnetic Exploration Of The Crescent Formation, Washington: The Search For A Hidden Fault Near Dusk Point, Samuel G. Furmanski

Summer Research

The mafic rocks of the Olympic Peninsula, Washington, are part of an accreted terrane known as Siletzia which experienced transpressional stresses as far as 50 Ma ago in the early Eocene. The Peninsula has an accretion-thrust marine sedimentary interior and a mafic volcanic periphery juxtaposed along the Hurricane Ridge fault; a terrane-scale thrust fault. The mafic Crescent Formation (CF) can be subdivided into two units: The Lower Crescent member (LC) and the Upper Crescent member (UC) as defined by Tabor and Cady (1978). The LC consists of submarine basalt flows that have composition similar to mid-oceanic ridges with zircon fission-track …


Petrology Of The Eocene Goble Volcanics, Southwest Washington: An Early Phase Of The Cascade Arc, Clara Phipps, Jeffrey H. Tepper Jan 2019

Petrology Of The Eocene Goble Volcanics, Southwest Washington: An Early Phase Of The Cascade Arc, Clara Phipps, Jeffrey H. Tepper

Summer Research

The Eocene Goble Volcanics (GV), comprised of >1000 km2 of subaerial lavas and tuffs, are one of the most voluminous igneous formations in SW WA. Whole rock K-Ar ages of 45 to 32 Ma (Beck and Burr, 1979) suggest these rocks are an early expression of the Cascade arc, but their location is anomalous, lying between oceanic Crescent Fm basalts of the Siltezia terrane to the west and younger arc rocks to the east. The goals of this research are to determine the chemical and Sr-Nd isotopic traits of the GV and better establish the tectonic setting in which …


The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell Ladouceur Jan 2019

The Medicine Hat Block And The Assembly Of Laurentia: New Interpretations From Single-Grain Zircon Analyses, Blake Oswell Ladouceur

Electronic Theses and Dissertations

The Medicine Hat Block (MHB) is one of the core cratonic elements that amalgamated in the Paleoproterozoic to form Laurentia. However the role of the MHB in the formation of Laurentia is poorly constrained due to virtually all of the MHB being concealed by Proterozoic and younger supracrustal sequences limiting availability of data. The primary sources of samples from the MHB are 1) xenoliths of variable metamorphic grade including gneisses amphibolites and meta-plutonic rocks collected from Eocene volcanic rock; and 2) similar lithologies recovered from boreholes that penetrate to the MHB basement. Previous work on samples from the MHB yielded …


Exploration For Alteration Halos Around The Ag-W Deposits In Southeastern Missouri, Usa, Daniel Joseph Warbritton Jan 2019

Exploration For Alteration Halos Around The Ag-W Deposits In Southeastern Missouri, Usa, Daniel Joseph Warbritton

Masters Theses

"The St. Francois Mountains in SE Missouri are an extensive terrane of granitic ring complexes and associated rhyolites. They were an important source of Ag, W, and Sn and mined intermittently from the 1800s until the 1950s. The Ag-W ores occur in the Silvermine Granite and rhyolite roof rocks. The deposits are classified as a xenothermal ore system with mineralization occurring in quartz veins and surrounding greisen (up to 2.5 m). Exploration for hydrothermal ore deposits often focuses on the identification of alteration halos in the surrounding host rocks. In the vast majority of xenothermal ore deposits, such as in …


The Origin Of An Archean Batholith In Michigan’S Upper Peninsula, Brandi Petryk Jan 2019

The Origin Of An Archean Batholith In Michigan’S Upper Peninsula, Brandi Petryk

Dissertations, Master's Theses and Master's Reports

The Southern Complex is part of the Archean Superior Province in the Upper Peninsula of Michigan and includes a batholithic sized body of Archean high-K megacrystic granitoid rocks informally called the Bell Creek granite. U-Pb zircon ages of the granitoid from previous studies suggest an emplacement age of ~2.6 Ga (Tinkham, 1997). Based on those ages the Bell Creek granite formed around the Archean-Proterozoic transition. This transition is a crucial time period in Earth’s history for crustal growth because of the onset of subduction and increased sedimentary environments at the end of the Archean (Taylor and McLennan, 1995). In this …


Biodiversity And Distribution Of Benthic Foraminifera In Harrington Sound, Bermuda: The Effects Of Physical And Geochemical Factors On Dominant Taxa, Nam Le Jan 2019

Biodiversity And Distribution Of Benthic Foraminifera In Harrington Sound, Bermuda: The Effects Of Physical And Geochemical Factors On Dominant Taxa, Nam Le

Honors Theses

Harrington Sound, Bermuda, is a nearly enclosed lagoon acting as a subtropical/tropical, carbonate-rich basin in which carbonate sediments, reef patches, and carbonate-producing organisms accumulate. Here, one of the most important calcareous groups is the Foraminifera. Analyses of common benthic orders, including miliolids (Quinqueloculina and Triloculina spp.) and rotaliids (Homotrema rubrum, Elphidium spp., and Ammonia beccarii), are essential in understanding past and present environmental conditions affecting the island's coastal environment. These taxa have been studied previously; however, factors explaining their individual patterns of abundance in the Sound are not well detailed. The goal of this study is …


Late Devonian Sedimentary Record Of Appalachian Tectonics And Erosion: Geochronology And Geochemistry Of Detrital Muscovite And Zircon From Central Pennsylvania Strata, Cole T. Gardner Jan 2019

Late Devonian Sedimentary Record Of Appalachian Tectonics And Erosion: Geochronology And Geochemistry Of Detrital Muscovite And Zircon From Central Pennsylvania Strata, Cole T. Gardner

Honors Theses

Foreland basin sediment deposition in North-Central Pennsylvania during Late Devonian time records erosion of hinterland source terranes exhumed during regional plate convergence, including the collisional Acadian orogeny. The Catskill clastic wedge preserves a coarsening-upwards stratigraphic succession from marine to fluvial environments associated with sediment progradation and sea-level regression, yet depositional timescales and quantitative provenance data are largely unconstrained.

Detailed facies analysis of eight outcrops spanning >2 km of stratigraphy in Lycoming Co., Pennsylvania documents distinct upsection changes, interpreted to reflect changes in depositional environments consistent with previous sedimentology of the Catskill clastic wedge. Stratigraphy displays a transition from nearshore marine …


Groundwater Hydrogeolgy And Hydrochemistry Of Karst Springs In The Eastern Peninsula Of Fort Hood Military Installation, William Scribner Welles Dec 2018

Groundwater Hydrogeolgy And Hydrochemistry Of Karst Springs In The Eastern Peninsula Of Fort Hood Military Installation, William Scribner Welles

Electronic Theses and Dissertations

The eastern peninsula of Fort Hood Military Installation is underlain by a complex karst spring network. These springs are a primary water source in a protected habitat for endangered songbirds, which has only recently begun to be fully investigated. These Fredericksburg Group springs express both epigenetic and hypogenetic karst signatures. The study area is part of a paleo reef trend, a hydraulically disconnected segment of the northern section of the Edwards Aquifer. This study utilized standard ion index values, repeated measures, and principal component analyses on the chemical profiles of six perennial springs to classify spring water sources and their …


Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range, Justin T. Wilgus Oct 2018

Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range, Justin T. Wilgus

Earth and Planetary Sciences ETDs

Metamorphic core complexes (MCC) are distinctive uplifts that expose deeply exhumed and deformed crustal rocks due to localized extensional deformation. Consequently, their detailed structure provide a window into deep crustal mechanics. The North American Cordillera contains numerous MCC, one of which is the Ruby Mountains core complex (RMCC) located in the highly extended northern Basin and Range. To constrain the extent to which anisotropy below the RMCC deviates from the regional Basin and Range average and test the depth dependence of crustal anisotropy we conduct a radial anisotropy investigation below the RMCC and surrounding northern Basin and Range. Data from …


Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden Oct 2018

Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden

Masters Theses & Specialist Projects

The geology of Ethiopia is dominated by the Ethiopian Plateau that is similar in elevation to, but aerially larger than, the Colorado Plateau. Several rivers have incised through the plateau, creating gorges that reach up to 1.5 km in depth. The plateau uplifted to its current elevation and was subsequently incised sometime after the Oligocene flood basalt event that signaled the arrival of the African Superplume below Kenya and Ethiopia. Due to its size and extent, published climate modeling has indicated that Late Cenozoic plateau formation could have been a driving force in the East African Cenozoic climate changes. Although …


Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman Jul 2018

Review Of Curbing Catastrophe: Natural Hazards And Risk Reduction In The Modern World, Kira H. Hamman

Numeracy

Timothy H. Dixon. 2017. Curbing Catastrophe: Natural Hazards and Risk Reduction in the Modern World. (New York, NY: Cambridge University Press) 300 pp. ISBN 978-1108113663.

In Curbing Catastrophe, Timothy H. Dixon explores commonalities among natural disasters like Hurricane Katrina, the 2010 earthquake in Haiti, and the meltdown at Fukushima. He identifies communication failure between scientists and policy makers as a major culprit in the devastation that results from such events and offers strategies for improving that communication. He includes optional in-depth scientific and quantitative examinations of the events and the resulting devastation, making the book appropriate for use …


Geochemical And Petrological Investigation Of The Prospective Ni-Cu-Pge Mineralization At The Echo Lake Intrusion In The Upper Peninsula Of Michigan, Usa, Alexander J. Koerber Apr 2018

Geochemical And Petrological Investigation Of The Prospective Ni-Cu-Pge Mineralization At The Echo Lake Intrusion In The Upper Peninsula Of Michigan, Usa, Alexander J. Koerber

Masters Theses

The Echo Lake Intrusion is located in Houghton and Ontonagon counties in the Upper Peninsula (UP) of Michigan. The intrusion is approximately 200 m below the surface and covers approximately 18 km2 in lateral extent. It is associated with the magmatic activities of a 1.1 Ga geologic event called the Midcontinent Rift. The rift is responsible for the formation of Ni-Cu ± PGE deposits in the Lake Superior Region. Based on its association with the Midcontinent Rift and a Cu and PGE enriched layer, the Echo Lake intrusion is identified as a prospect for an economic magmatic sulfide deposit.

The …


Identifying The Origins Of Volcanic Ash Deposits Using Their Chemical And Physical Compositions, Emmanuel Soto Mar 2018

Identifying The Origins Of Volcanic Ash Deposits Using Their Chemical And Physical Compositions, Emmanuel Soto

FIU Electronic Theses and Dissertations

Recent ocean sediments collected offshore Chile by Ocean Drilling Program Leg 202 contained layers of volcanic ash of unknown origin. These deposits may have originated from sources in the Southern Volcanic Zone (SVZ) within the Andean Volcanic Belt to the east, or from explosive volcanoes in the southwestern Pacific transported by westerly prevailing winds. In this study, mineral and glass textures and compositions of Leg 202 ashes were evaluated to try to determine the sources of the ash layers. Ash fragments were imaged and analyzed for major elements using an SEM with X-Ray detector and for trace elements using LA-ICPMS. …


Arctic And North Atlantic Paleo-Environmental Reconstructions From Lake Sediments, Gregory A. De Wet Nov 2017

Arctic And North Atlantic Paleo-Environmental Reconstructions From Lake Sediments, Gregory A. De Wet

Doctoral Dissertations

ABSTRACT

ARCTIC AND NORTH ATLANTIC PALEO-ENVIRONMENTAL RECONSTRUCTIONS FROM LAKE SEDIMENTS MAY 2017 GREGORY A. DE WET, B.Sc., BATES COLLEGE M.Sc., UNIVERSITY OF MASSSCHUSETTS, AMHERST Ph.D., UNIVERSITY OF MASSACHUSETTS, AMHERST Directed by: Drs. Raymond S. Bradley and Isla S. Castañeda There are few fields in the discipline of Earth Science that hold more relevancy in 2017 than studies of earth’s climate. Called the “perfect problem” considering its complexity and magnitude, climate change will continue to be one of the greatest challenges humanity will face in the 21st century. And while numerical models provide valuable information on conditions in the future, …


Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, Forrest Christopher Driscoll Aug 2016

Role Of Sorting On The Composition Of Siliciclastic Sediment: Implications For Interpreting Provenance After Limited Transport In An Arid Climate, Forrest Christopher Driscoll

Masters Theses

This study tested whether transport distances (< 500 m) have the capacity to shape the geochemistry of sediments across multiple grain-size populations due to sorting derived from a single source. In the Stepladder Mountains, Mojave Desert, CA, a < 1 km2 [square kilometers] watershed allows for a controlled study to understand how modern sediments acquire their composition from a single granodioritic source in an arid climate where there is no chemical weathering. Sediments are naturally sorted into distinct grain-size populations, with modes ranging from very fine sand to gravel within a single, alluvial channel. Sediment samples representative of each population were petrographically and geochemically analyzed in order to test the effectiveness of commonly used discrimination diagrams. Sediments became proportionally enriched in plagioclase and biotite and depleted in K-feldspar and quartz with decreasing grain …


Geochemistry And Origins Of Thermal Springs Waters Of The Olympic Peninsula And Cascade Range, Washington, Jon Kenneth K. Golla Jan 2016

Geochemistry And Origins Of Thermal Springs Waters Of The Olympic Peninsula And Cascade Range, Washington, Jon Kenneth K. Golla

Summer Research

The state of Washington contains 98 low temperature (surface temperatures between ~ 20 - 50 oC) geothermal springs, which are powered by the convective circulation of groundwater that is heated by the natural heat of the Earth. These systems operate in a cycle that begins when precipitation percolates downward into the subsurface and comes in contact with a heat source. Subsequently the heated water returns to the surface, in most cases, having interacted chemically with rocks in the reservoir and/or along its ascent path. Surveys done by the USGS between the 1970s – early 1990s show there is significant …