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Full-Text Articles in Physical Sciences and Mathematics

Comparative Lineament And Geomorphic Analysis Of Chaotic Terrains And Noctis Labyrinthus, Mars, Sarah A. Walton Dec 2023

Comparative Lineament And Geomorphic Analysis Of Chaotic Terrains And Noctis Labyrinthus, Mars, Sarah A. Walton

Electronic Theses and Dissertations

Noctis Labyrinthus (NL) is an extensional trough network connecting the Tharsis rise and Valles Marineris on Mars. Chaotic terrains are a group of polygonally-fractured surface features commonly associated with subsidence due to rapid fluid loss within the subsurface. Polygonal surface patterns are seen at both sites, where geometric topographic highs are bounded by low troughs. Lineaments, topography, and geomorphology of NL and chaotic terrains were analyzed to determine tectonics and fluid influence in the formation and evolution of both sites. NL shows preferential fracture patterns associated with regional extension. Lineaments within chaotic terrains do not show cumulative preferential trends but …


Rheological Bridge Zones: A New Perspective To Explore Strain Localization And Rock Rheological Weakening, He Feng Dec 2023

Rheological Bridge Zones: A New Perspective To Explore Strain Localization And Rock Rheological Weakening, He Feng

Electronic Theses and Dissertations

Strain localization, a ubiquitous geological phenomenon, emerges when rock undergoes extensive weakening and accommodates disproportionate deformation. This phenomenon spans from brittle faulting to viscous flow, known as shear zones. Despite its prevalence, discussions on weakening primarily center on highly strained samples, rather than the initial deformation state. This research delves into the evolution of localization and rheology in intact rocks.

Heterogeneous mechanical properties within the lithosphere vary based on mineralogy, microstructure, and environmental conditions. Chapter 2 characterizes microscale structures termed "bridge zones." These zones, observed through optical and electron microscopy, exhibit distinctive morphologies. Comprising fine-grained aggregates, bridge zones link weak …


Investigating Mercer's Paradox: A 10be Chronology Of Moraines Deposited During The Last Glaciation At Soda Lake, Wind River Range, Wyoming, U.S.A., Lauren M. Woods Aug 2023

Investigating Mercer's Paradox: A 10be Chronology Of Moraines Deposited During The Last Glaciation At Soda Lake, Wind River Range, Wyoming, U.S.A., Lauren M. Woods

Electronic Theses and Dissertations

Here I use geomorphic mapping and 10Be surface-exposure dating to address the paradox that lies within the general understanding of the mechanisms driving ice-age climate and glacial cycles. The long-standing and widely accepted Murphy-Milankovitch hypothesis suggests glacial cycles are controlled by the local intensity of summer-time insolation. By this hypothesis, glacier maxima should be achieved at times of low insolation intensity and asynchronously between the polar hemispheres, a pattern which is inconsistent with the glacial geomorphic record. The 10Be chronology I have constructed of moraines at Soda Lake, Wind River Range, Wyoming, U.S.A. shows nine glacial advances to …


Reservoir Characterization Of The Utica Shale Play Using Well Log Data In Columbiana, Ohio, Tyler L. West Aug 2023

Reservoir Characterization Of The Utica Shale Play Using Well Log Data In Columbiana, Ohio, Tyler L. West

Electronic Theses and Dissertations

The Ordovician Utica shale play is rapidly developing throughout the Appalachian Basin. The play is a mixed carbonate-siliciclastic system that grades from primarily carbonates at its base in the Lexington/Trenton limestones into primarily shale within the Utica shale. As of January 2021, it is the third highest-producing dry shale gas play in the contiguous U.S., although it is known to produce wet gas and oil in various parts of the basin. In addition to being an unconventional reservoir, the Utica shale, an informal unit in Ohio where the main fairway is located, is a known source rock for much of …


First-Row Transition Element Distribution Across The Blueschist-Eclogite Transition: A Case Study From New Caledonia, Natalie M. Harmon Dec 2022

First-Row Transition Element Distribution Across The Blueschist-Eclogite Transition: A Case Study From New Caledonia, Natalie M. Harmon

Electronic Theses and Dissertations

The first-row transition elements (FRTE), namely Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, are potential redox tracers in the solid Earth due to their general compatibility during crustal processes, and the redox-sensitive nature of certain elements. Despite widespread interest in the FRTEs, their distribution and behavior in subduction zones, particularly across the blueschist-eclogite transition, are still poorly constrained. New Caledonia preserves a prograde subduction zone with largely coherent continuous progression in metamorphic grade. Although the metamorphic sequence has been disrupted to some extent, this is the closest natural example of blueschist and eclogite that was sourced …


Silting Dynamics And Metal Contaminants In The Georgetown Inner Harbor, Ezekiel Wil Meyers Dec 2022

Silting Dynamics And Metal Contaminants In The Georgetown Inner Harbor, Ezekiel Wil Meyers

Electronic Theses and Dissertations

The Georgetown inner harbor is an abandoned oxbow-like river loop and a vital historic site with a wealth of traditional businesses and heavy local industry located within Winyah Bay. Since the modification of the Sampit River in 1949, chronic rapid silting has plagued the inner harbor. With these substantial amounts of fine-grained material accumulating inside the inner harbor, business operations along the waterfront, navigational and maritime operations, and contamination within the harbor are of major concern. The goals of this study were to (a) understand the silting dynamics inside the inner harbor, (b) identify heavy metals which might be of …


Extraction, Analysis, And Comparison Of Microplastics In Sc Marsh Substrates, Austin G. Sige Dec 2022

Extraction, Analysis, And Comparison Of Microplastics In Sc Marsh Substrates, Austin G. Sige

Electronic Theses and Dissertations

The global, rapid increase in plastic production is a widespread problem for coastal environments such as marshes that present favorable conditions for plastic retention. This study looked at the microplastic abundance within three previously unstudied South Carolina marshes located in Myrtle Beach, Murrells Inlet, and Waties Island. A comparison between the microplastic types and abundances between locations provided knowledge about the impacts of sediment composition (sand, silt, clay, and organic matter) on microplastic sequestration. This study also produced a novel microplastic extraction methodology for cohesive marsh sediment that used elutriation to effectively break apart aggregates prior to chemical digestion and …


Geochemical Characterization Of The Louann Salt, Puma Field, Green Canyon, Gulf Of Mexico Basin – Using Xrf And Xrd, Brian Lesh Aug 2022

Geochemical Characterization Of The Louann Salt, Puma Field, Green Canyon, Gulf Of Mexico Basin – Using Xrf And Xrd, Brian Lesh

Electronic Theses and Dissertations

The Jurassic-aged Louann Salt is an evaporite sequence deposited in the Gulf of Mexico Basin (GOMB). It is an important component of the GOMB petroleum system and influences the facies pattern in overlying strata and the distribution of petroleum stratigraphic traps. The Louann Salt is composed primarily of halite with intercalated anhydrites and silty or sandy-halite intervals, with overall thicknesses in excess of four kilometers (~13,000 feet). Suture zones occur intermittently within the Louann Salt, formed by the collision of allochthonous evaporite layers. The mineralogy and geochemistry of the suture zones are currently understudied and can be hazardous during drilling …


Geochemical Characterization Of The Bone Spring Formation, Delaware Basin, Using Chemostratigraphy And Integrated Petrophysics, David Tonner Aug 2022

Geochemical Characterization Of The Bone Spring Formation, Delaware Basin, Using Chemostratigraphy And Integrated Petrophysics, David Tonner

Electronic Theses and Dissertations

The Delaware Basin forms part of West Texas's and New Mexico’s famous petroleum-generating Permian Basin. The Bone Spring Formation is a prolific hydrocarbon producer within this basin, creating one of the world’s richest oil shales. This formation has lithological sequences that are characterized by repeating carbonate and siliciclastic intervals of a third-order cycle which can largely be correlated to highstand and lowstand systems tracts, respectively. Lithological complexity and facies change are manifested by debris flows, turbidites, and slumps. In addition to glacio-eustasy, both tectonism and broader Milankovitch cycles have influenced the depositional history. Previous investigations have utilized cores and wireline …


Stratigraphic Analysis Of The Capps Limestone In The North Norton Oil Field In Runnels County, Texas, William Thompson Dec 2021

Stratigraphic Analysis Of The Capps Limestone In The North Norton Oil Field In Runnels County, Texas, William Thompson

Electronic Theses and Dissertations

The Desmoinesian (Middle Pennsylvanian) Capps Limestone Member of the Mineral Wells Formation is a carbonate reservoir located in North Central Texas. It consists of interbedded limestone, sandstone, and shale units. Much of the Capps Limestone exists in the subsurface of Brown, Coleman, Runnels, Coke, Nolan, and Taylor counties, however, the Capps Limestone outcrops on the surface in Brown, Eastland, and Palo Pinto counties.

The cored interval from Runnels County was deposited in a marginal marine environment during the Middle Pennsylvanian Period. Although the Capps Limestone was first described in the 1890s, there is still much to be discovered about its …


Detailed Structural And Stratigraphic Analysis Of The Salt-Sediment Interactions On Top Of The Wheeler Dome Salt Tongue, Mississippi Canyon Area, Gulf Of Mexico, Ryan Jaska Nov 2021

Detailed Structural And Stratigraphic Analysis Of The Salt-Sediment Interactions On Top Of The Wheeler Dome Salt Tongue, Mississippi Canyon Area, Gulf Of Mexico, Ryan Jaska

Electronic Theses and Dissertations

The Mississippi Canyon is in the northeastern part of the Gulf of Mexico, south of the state of Mississippi. In this area, there are many different salt structures present including salt canopies, diapirs, and salt pillows. The Callovian aged Louann Salt covers this area and is the cause of many of the salt structures and structures of the overlying formations seen in Gulf of Mexico today. Salt is mobile when subjected to stress from overlying sediment and gravity. Stress will force the salt to not only move upward, but to also move down slope deeper into adjacent basins through the …


Numerical Modeling Of Controlling Factors For Formation Of Unconformity-Related Uranium Deposits In Sedimentary Basins, Jiayue Shen Oct 2021

Numerical Modeling Of Controlling Factors For Formation Of Unconformity-Related Uranium Deposits In Sedimentary Basins, Jiayue Shen

Electronic Theses and Dissertations

Unconformity-related uranium (URU) deposits are the most profitable uranium deposits in the world. Among those deposits, the Athabasca Basin hosts the world’s largest high-grade uranium deposits. A series of numerical experiments regarding the effect of uranium source location, fault location, and fault dip angle on the formation of URU deposits have been conducted by using software TOUHREACT.

Simulation results suggest that although both sandstone-sourced and basement-sourced models can generate economical deposits, basement-sourced models are more likely to form larger deposits since uranium-carrying fluid only needs to move a shorter distance to reach the structural trap for further ore forming reaction. …


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 …


Spatial Analyses Of Gray Fossil Site Vertebrate Remains: Implications For Depositional Setting And Site Formation Processes, David Carney Aug 2021

Spatial Analyses Of Gray Fossil Site Vertebrate Remains: Implications For Depositional Setting And Site Formation Processes, David Carney

Electronic Theses and Dissertations

This project uses exploratory 3D geospatial analyses to assess the taphonomy of the Gray Fossil Site (GFS). During the Pliocene, the GFS was a forested, inundated sinkhole that accumulated biological materials between 4.9-4.5 mya. This deposit contains fossils exhibiting different preservation modes: from low energy lacustrine settings to high energy colluvial deposits. All macro-paleontological materials have been mapped in situ using survey-grade instrumentation. Vertebrate skeletal material from the site is well-preserved, but the degree of skeletal articulation varies spatially within the deposit. This analysis uses geographic information systems (GIS) to analyze the distribution of mapped specimens at different spatial scales. …


Using An Inventory Of Unstable Slopes To Prioritize Probabilistic Rockfall Modeling And Acid Base Accounting In Great Smoky Mountains National Park, Thomas A. O'Shea Aug 2021

Using An Inventory Of Unstable Slopes To Prioritize Probabilistic Rockfall Modeling And Acid Base Accounting In Great Smoky Mountains National Park, Thomas A. O'Shea

Electronic Theses and Dissertations

An inventory of unstable slopes along transportation corridors and performance modeling are important components of geotechnical asset management in Great Smoky Mountains National Park (GRSM). Hazards and risk were assessed for 285 unstable slopes along 151 miles of roadway. A multi-criteria model was created to select fourteen sites for two-dimensional probabilistic rockfall simulations and Acid Base Accounting (ABA) tests. Simulations indicate that rock material would likely enter the roadway at all fourteen sites. ABA test results indicate that influence of significant acid-producing potential is generally confined to slaty rocks of the Anakeesta Formation and graphitic schist of the Wehutty Formation. …


Analysis And Risk Estimation Of High Priority Unstable Rock Slopes In Great Smoky Mountains National Park, Tennessee And North Carolina, Samantha Farmer Aug 2021

Analysis And Risk Estimation Of High Priority Unstable Rock Slopes In Great Smoky Mountains National Park, Tennessee And North Carolina, Samantha Farmer

Electronic Theses and Dissertations

Great Smoky Mountains National Park (GRSM) received 12.5 million visitors in 2020. With a high traffic volume, it is imperative roadways remain open and free from obstruction. Annual unanticipated rockfall events in GRSM often obstruct traffic flow. Using the Unstable Slope Management Program for Federal Land Management Agencies (USMP for FLMA) protocols, this study analyzes high priority unstable rock slopes through 1) creation of an unstable slope geodatabase and 2) generation of a final rockfall risk model using Co-Kriging from a preliminary risk model and susceptibility model. A secondary goal of this study is to provide risk estimation for the …


Precambrian Basement Influence On The Deposition Of The Upper Ordovician Utica Shale Play In East Central Ohio, William Kaleb Kirk Jun 2021

Precambrian Basement Influence On The Deposition Of The Upper Ordovician Utica Shale Play In East Central Ohio, William Kaleb Kirk

Electronic Theses and Dissertations

The Ordovician Utica shale play is a major oil and gas producing interval in the Appalachian Basin. The Utica shale play can be found as far as New York and Canada and to the south into Indiana and Kentucky. The play consists of the Trenton/Lexington limestones, Point Pleasant Formation, and Utica shale. The shallow marine fossiliferous limestones of the Trenton and shallow marine shaley limestones of the Lexington are overlain by an interbedded shale and limestone of the Point Pleasant Formation, which grade into the deeper marine interbedded shales and limey shales of the Utica. These formations are highly heterogeneous, …


Mineralogical Restrictions On Porosity In The Taylor Sand Of The Cotton Valley Group, Northern Louisiana Salt Basin, Claiborne Parish, Louisiana, Kaleb C. Mcclain Jun 2021

Mineralogical Restrictions On Porosity In The Taylor Sand Of The Cotton Valley Group, Northern Louisiana Salt Basin, Claiborne Parish, Louisiana, Kaleb C. Mcclain

Electronic Theses and Dissertations

The Cotton Valley Group has been targeted for hydrocarbons since the 1940s. However, the reservoir was initially considered uneconomical to drill due to its low permeability and porosity. Since then, recent technological advances in hydraulic fracturing have allowed the Cotton Valley Sandstone members to become prolific, profitable plays, renewing interest in drilling and exploration across the northwest/northern Louisiana region.

In this research, mineralogical restrictions on the porosity in the Lower Taylor Sand of the Cotton Valley Group were studied from core (10,035’ft/3,059m -10,150’ft/3,094m) from Blackburn Field, northwest Claiborne Parish. Twelve samples were taken at intervals throughout the Taylor Sand, starting …


Deposition And Diagenesis Of The Blossom Sand, Panola County, Texas, Hannah Chambers Jun 2021

Deposition And Diagenesis Of The Blossom Sand, Panola County, Texas, Hannah Chambers

Electronic Theses and Dissertations

The Late Cretaceous Blossom Sand within the Austin Group is a historic gas reservoir in the East Texas basin, located at depths of approximately 2,000 ft below the surface. Since the discovery of the Carthage Field in 1918 in the East Texas Basin, the Blossom Sand has produced approximately 26 BCF of gas with minor amounts of oil. Despite its notoriety in the Carthage Field, there is very little research that has been conducted on this unit, although it crops out in northeast Texas and is found in the subsurface of southwest Arkansas, western Louisiana, and the East Texas Basin. …


Geochemical Characterization Of The Utica Shale Play Using Xrf-Based Chemostratigraphy In Ohio, Barbara Kemeh, Julie M. Bloxson May 2021

Geochemical Characterization Of The Utica Shale Play Using Xrf-Based Chemostratigraphy In Ohio, Barbara Kemeh, Julie M. Bloxson

Electronic Theses and Dissertations

The Utica shale is an extensive gas shale play within the Appalachian Basin, expanding from Quebec through New York, into Pennsylvania, West Virginia and Ohio. Currently a target for gas exploration, it is also the source rock for much of the Paleozoic reservoirs throughout the basin. However, the Utica-Point Pleasant lithology varies significantly across the Appalachian Basin which can make it challenging to characterize.

The Utica shale Play consists of the Trenton/Lexington Limestones, Point Pleasant Formation and Utica shale. The Point Pleasant Formation and Utica shale are often grouped together, especially in Ohio because they are difficult to visually distinguish …


Gravel Geology And Muskoxen Paleontology Of A Late Pleistocene Fossil Site In Saltville, Virginia, Nickolas A. Brand May 2021

Gravel Geology And Muskoxen Paleontology Of A Late Pleistocene Fossil Site In Saltville, Virginia, Nickolas A. Brand

Electronic Theses and Dissertations

Two distinct studies within the Saltville Valley of southwestern Virginia revealed insights into local Pleistocene geology and paleontology. A variety of analytical techniques were applied to gravel deposits within the paleontological site of SV-5/7 that revealed this unit is very poorly sorted, has a subangular matrix, and contains significant components of silt and sand in addition to rounded cobbles. These results suggest that rather than being deposited by fluvial processes as previously suggested, these gravels were likely the result of one or many debris flows. Additionally, the identity of fossil muskoxen from Saltville was reassessed using cranial and dental material. …


Sub-Surface Structural Analysis Of The Appalachian Basin In Morrow County, Ohio, Adrian Isaiah-Sias Valdez May 2021

Sub-Surface Structural Analysis Of The Appalachian Basin In Morrow County, Ohio, Adrian Isaiah-Sias Valdez

Electronic Theses and Dissertations

Located in the western most region of the Appalachian Basin, Morrow County, Ohio, was once one of the largest oil-producing regions in the nation and continually produces today. To date, approximately 30 million barrels of oil and 6.5 billion cubic feet of gas have been produced, primarily from the Copper Ridge Dolomite. Past studies suggest that regional remnant doming within the Copper Ridge accounts for production, however it is hypothesized that faulting within the basement rock exerts an important control on trapping and migration of hydrocarbons. In order to gain insight into the underlying structure and the causes of significant …


Characterization And Delineation Of Potential Evaporite Geohazards Using Electrical Resistivity Methods Along Fm 2185, Culberson County, Texas, Lenora Diane Perkins May 2021

Characterization And Delineation Of Potential Evaporite Geohazards Using Electrical Resistivity Methods Along Fm 2185, Culberson County, Texas, Lenora Diane Perkins

Electronic Theses and Dissertations

Extensive karst development within the Delaware Basin of West Texas and southeastern New Mexico poses a significant geohazard threat to infrastructure. Dissolution of regional evaporite strata have led to manifestations of karst geohazard phenomena including sinkholes, subsidence features, and caves. The study area is located within the Gypsum Plain in Culberson County, Texas, and includes outcrops of Castile and Rustler strata that host gypsum karst geohazards. Land reconnaissance surveys conducted during the summer of 2019 documented numerous surficial manifestations of karst features proximal to Farm to Market Road 2185 (FM 2185). In combination with traditional survey techniques, electrical resistivity methods …


Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark Jan 2021

Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark

Electronic Theses and Dissertations

Bauxite is a heavily-mined aluminum ore that forms through the relative depletion of silica to aluminum. In North Mississippi, bauxite occurring within the Upper Midway and Lower Wilcox groups has been the subject of study for over a century. Despite the abundance and duration of research, controversy surrounds the subjects of bauxite genesis and economic value. The last detailed study of North Mississippi bauxite was in the 1980’s, so the goal of this project is to apply newly available technologies and modern hypotheses on bauxite formation to refine and obtain new data. Fieldwork observations yielded pisoliths, horizonation, and possible rhizoliths, …


Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle Dec 2020

Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle

Electronic Theses and Dissertations

The Mesoproterozoic intrusive contact between the ~1.1 Ga anorogenic Town Mountain Granite and the ~1.3 Ga Packsaddle Schist is a gradational contact exhumed within the Llano uplift. This contact is exposed along the southeastern margin of the Enchanted Rock batholith in central Texas. Field observations, hand sample and thin section petrography, and handheld X-ray fluorescence analysis of hand samples were used to characterize the gradational nature of this contact at multiple scales. The style of gradation between the Town Mountain Granite and Packsaddle Schist varies throughout the study area, containing both injection and permeation. The complex relationships observed at the …


Inter-Annual To Inter-Decadal Spatiotemporal Effects Of Storm And Nourishment Events In North Myrtle Beach, South Carolina, Christina Mary Boyce Dec 2020

Inter-Annual To Inter-Decadal Spatiotemporal Effects Of Storm And Nourishment Events In North Myrtle Beach, South Carolina, Christina Mary Boyce

Electronic Theses and Dissertations

No abstract provided.


Delineating Of The Utica Shale/Point Pleasant Formation Play System To Determine Influence Of The Precambrian Basement In Northeastern Ohio, Jarrod R. Bridges Dec 2020

Delineating Of The Utica Shale/Point Pleasant Formation Play System To Determine Influence Of The Precambrian Basement In Northeastern Ohio, Jarrod R. Bridges

Electronic Theses and Dissertations

The Utica Shale/Point Pleasant Formation system has recently become a highly developed unconventional target for oil and natural gas production, leading to an increased desire for knowledge of the controls on deposition of this system. Precambrian basement features have long been known to affect deposition of older strata near these features across Ohio, but the effects of far field tectonics is not fully agreed upon. Precambrian faults and lineaments are known to exist and have been mapped, but are thought to have ceased their influence on deposition by the time of the Knox unconformity during the Cambrian. In the case …


The Persistence Of Acid Mine Drainage At An East Texas Coal Mine, Sarah Zagurski Dec 2020

The Persistence Of Acid Mine Drainage At An East Texas Coal Mine, Sarah Zagurski

Electronic Theses and Dissertations

The objective of this study was to estimate the time it will take for acid forming materials (pyrite) to be weathered to a state of equilibrium and thus cease to produce acid in ground and surface waters within Oak Hill Mine. This was accomplished using an ex-situ kinetic leaching study incorporating a humidity cell in a controlled laboratory setting. Leaching was conducted on soil cores obtained from the vadose zone at Oak Hill Mine and the humidity cell was used to accelerate oxidation of the pyrite within the cores.

An in-situ field study was also conducted that monitored groundwater conditions …


Stratigraphy, Petrology, Diagenesis, Paleontology, And Depositional Environments Of The Harrisburg Member Of The Kaibab Formation In Northern Arizona And Southern Utah, Zachery T. Case Dec 2020

Stratigraphy, Petrology, Diagenesis, Paleontology, And Depositional Environments Of The Harrisburg Member Of The Kaibab Formation In Northern Arizona And Southern Utah, Zachery T. Case

Electronic Theses and Dissertations

The Kaibab Formation has two members, the Fossil Mountain Member below and the Harrisburg Member above. They were deposited in shallow-marine shelf to restricted coastal settings. Stratigraphically above are the Rock Canyon Conglomerate and the Moenkopi Formation; consisting of the Timpoweap and Lower Red members; which are the only members present in the study area. The Rock Canyon Conglomerate was deposited in depressions and as a regolith. The Timpoweap and Lower Red members were deposited in shallow marine to tidal environments.

Nine stratigraphic units were identified in the Harrisburg Member. Units one, two, three, five, six, seven, and nine are …


Sulfur And Trace Metal Cycling At Convergent Margins, Jesse B. Walters Aug 2020

Sulfur And Trace Metal Cycling At Convergent Margins, Jesse B. Walters

Electronic Theses and Dissertations

Subduction zones are the site of long-term chemical exchange between Earth’s surface and interior geochemical reservoirs. Subducting slabs are progressively depleted in volatiles and other mobile elements through dehydration and melting reactions. These elements are then introduced to the mantle wedge and volcanic arc. One consequence of this cycle is that volcanic arcs produce the most oxidized magmas on Earth. Sulfur, which exhibits a range in valence states from S2- to S6+, is one of the few elements in the subducting slab capable of oxidizing the arc and mantle wedge. Sulfides in the slab may also act …