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Earth and Planetary Sciences ETDs

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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 …


Hydrochemistry Of An Alpine Karst System, Northern New Mexico: Las Huertas, Kambray A. Townsend Oct 2023

Hydrochemistry Of An Alpine Karst System, Northern New Mexico: Las Huertas, Kambray A. Townsend

Earth and Planetary Sciences ETDs

Las Huertas in the Sandia Mountains relies on snowmelt, monsoonal recharge, and groundwater inputs. Our hypothesis, the proportion of groundwater contribution varied spatially and temporally, was assessed by observing travertine and multiple geochemical tracers to differentiate water balance components. We report 26 samples from 13 locations (sampled between 2021-2023). Major ion and isotopic analysis indicated Las Huertas headsprings vary spatially. Capulin Spring has higher salinity; major ions suggest recharged waters are a mix of CaCO3-rich and sulfate-chloride-containing water. The proportion of groundwater to spring discharge is a mix of winter and summer precipitation. Travertine supersaturation is seasonal, with variations downstream, …


Applications Of Observational Seismology: Insights Into Volcanic And Near Surface Processes, Justin T. Wilgus Aug 2023

Applications Of Observational Seismology: Insights Into Volcanic And Near Surface Processes, Justin T. Wilgus

Earth and Planetary Sciences ETDs

The field of observational seismology has made tremendous progress in the past two decades. This progress has been multi-faceted in form, but significant contributions emanated from 1) increases in both the quality and the quantity of seismic data 2) advances in computational power 3) advances in algorithmic capability, including machine learning. In this dissertation I report on three distinctly different seismic applications made possible by the aforementioned progress and discuss the insights these applications have provided in understanding volcanic and near surface processes of the Earth.

In the first chapter titled, “Shear Velocity Evidence of Upper Crustal Magma Storage Beneath …


Seismic Shadow Zone Investigation In The Upper Magma Reservoir Of The Yellowstone Caldera, Sarah Nolt-Caraway Aug 2023

Seismic Shadow Zone Investigation In The Upper Magma Reservoir Of The Yellowstone Caldera, Sarah Nolt-Caraway

Earth and Planetary Sciences ETDs

This study investigates whether the Yellowstone Caldera has enough melt to mute S-waves, creating a seismic shadow zone. Using a dense nodal deployment of ~650 stations, 7-9 earthquakes during the nodal deployment, and 21 broadband stations with 3,000-4,000 events per station; amplitude and noise maps, seismograms, and automatic phase picks probabilities from a deep learning model were analyzed to assess the potential role of melt, crustal attenuation, and noise in affecting body waves, particularly S-phases. The results are inconclusive, with unclear evidence whether observed amplitude decay is normal signal decay due to distance, noise-related, melt, or from scattering and intrinsic …


Seismic Analysis Of The Upper & Lower Falls Of The Yellowstone River, Loring Schaible Aug 2023

Seismic Analysis Of The Upper & Lower Falls Of The Yellowstone River, Loring Schaible

Earth and Planetary Sciences ETDs

Twelve years of concurrent hydrologic and continuous seismic data along with temporary seismic data demonstrate that the Upper and Lower Falls of the Grand Canyon of the Yellowstone River comprise a highly localized source of 0.5-5 Hz seismic energy that overwhelms anthropogenic contributions. In aggregate, seismic amplitude from 2008-2019 is linearly related to discharge with a correlation coefficient of 0.96. Repeated deviations from this linear relationship persist for 1-2 weeks prior to the date that Yellowstone Lake becomes clear of winter ice coverage. Seismic efficiency increases by ~50-250% during this period of ice-breakup, during which lake ice flows into the …


Assessing Ecological Relationships Among Late Triassic Vertebrates In Petrified Forest National Park, Alexandra Davis Apgar Jul 2023

Assessing Ecological Relationships Among Late Triassic Vertebrates In Petrified Forest National Park, Alexandra Davis Apgar

Earth and Planetary Sciences ETDs

The complex vertebrate ecosystem of the Late Triassic has not yet been fully understood, largely due to oversimplification of hypothesized trophic hierarchies and limited preservation of direct evidence of faunal interaction. Paleocommunity reconstruction attempts can also fall victim to taphonomic biases, time-averaging inaccuracies, and non-analogue paleoecologies. Utilizing a combination of PAIRS analysis and NMDS ordination, we highlight vertebrate faunal relationships within the Adamanian and Revueltian faunachrons of Petrified Forest National Park, assess the likelihood that these patterns have ecological rather than preservational drivers, and examine how these potential interactions may have been impacted by the Adamanian-Revueltian turnover event. We are …


Bulk Hydrogen Isotopes In Ordinary Chondrites, Michael J. Cato May 2023

Bulk Hydrogen Isotopes In Ordinary Chondrites, Michael J. Cato

Earth and Planetary Sciences ETDs

Bulk hydrogen isotopes in nominally anhydrous meteorites are a key component in our understanding of the distribution of hydrogen in our solar system, including the provenance of water on the Earth. Here, we develop a step-heated continuous-flow method to measure the bulk hydrogen isotopes in nominally anhydrous rocks and use this method to significantly increase the dataset of bulk hydrogen isotopes in ordinary chondrites, nearly doubling the number of equilibrated members. We found that as thermal alteration increases from petrologic type 3.0 to 4, there is a correlated decrease in both hydrogen content and isotope ratio, followed by no significant …


Evaluation Of Fluvial Package Amalgamation In Medial Dfs Deposits, Angel Peak Area, Nacimineto Formation, Sarah R. Rysanek Apr 2023

Evaluation Of Fluvial Package Amalgamation In Medial Dfs Deposits, Angel Peak Area, Nacimineto Formation, Sarah R. Rysanek

Earth and Planetary Sciences ETDs

Fluvial packages are the hypothetical groupings of facies that make up the fluvial succession consisting of channel belt sandstones and associated levee, floodplain, and avulsion deposits. This study attempted to describe a single fluvial package laterally using the new technologies of UAV imaging and 3D photogrammetry; however, amalgamation of channel belts and erosion from this amalgamation made long-distance lateral correlation difficult. This analysis of medial deposits in the Nacimiento Formation in the Angel Peak Area, Northwestern New Mexico evaluates the degree of amalgamation of fluvial packages across the study area while identifying facies associated with the hypothetical fluvial package. This …


Single-Crystal Elasticity Of Earth’S Mantle Transition Zone Minerals And High Pressure-Temperature Phase Equilibrium Experiments On Martian Basalts, Wenyi Zhou Nov 2022

Single-Crystal Elasticity Of Earth’S Mantle Transition Zone Minerals And High Pressure-Temperature Phase Equilibrium Experiments On Martian Basalts, Wenyi Zhou

Earth and Planetary Sciences ETDs

Wadsleyite and ringwoodite are major minerals in the Earth’s Mantle Transition Zone. Global and local seismic studies have detected strong lateral variations in seismic velocity and anisotropy in the Mantle Transition Zone, reflecting temperature and possible composition variations. Interpretation of these seismic observations requires knowledge of thermoelastic properties of wadsleyite and ringwoodite with different compositions (water and Fe contents) under high pressure-temperature conditions. In this dissertation, we have measured single-crystal elastic properties of wadsleyite and ringwoodite under high pressure-temperature conditions by Brillouin spectroscopy. Based on our measurements and previous experimental results, we further model the effects of water and Fe …


Induced Seismicity In The Raton Basin And Global Variability Of The 410-Km Discontinuity, Margaret E. Glasgow Nov 2022

Induced Seismicity In The Raton Basin And Global Variability Of The 410-Km Discontinuity, Margaret E. Glasgow

Earth and Planetary Sciences ETDs

Natural processes like mantle convection and plate tectonics dominate Earth’s seismic structure. Recently human activities have increasingly influenced the deformation of the shallow crust. In this dissertation, passive source seismology was used to constrain seismic discontinuities in the mantle transition zone and seismogenic structures in induced earthquake settings. Using a novel sampling method and uniform processing approach, I found the 410-km discontinuity is thermally and compositionally variable. Using a machine- learning approach, I found the three main zones of seismicity in the Raton Basin consist of short faults or fault segments with variable orientations. The zone that hosted a Mw …


A Rapid High-Precision Analytical Method For Triple Oxygen Isotope Analysis Of Co2 Gas Using Tunable Infrared Laser Direct Absorption Spectroscopy, Nathan Perdue, Zachary Sharp, David Nelson Jr., Rick Wehr, Christoph Dyroff Oct 2022

A Rapid High-Precision Analytical Method For Triple Oxygen Isotope Analysis Of Co2 Gas Using Tunable Infrared Laser Direct Absorption Spectroscopy, Nathan Perdue, Zachary Sharp, David Nelson Jr., Rick Wehr, Christoph Dyroff

Earth and Planetary Sciences ETDs

Rationale

The simultaneous analysis of the three stable isotopes of oxygen – triple oxygen isotope analysis – has become an important analytical technique in natural sciences. Determination of the abundance of the rare 17O isotope in CO2 gas using magnetic sector isotope ratio mass spectrometry is complicated by the isobaric interference of 17O by ­13C (13C16O16O and 12C16O17O both have mass 45 amu). A number of analytical techniques have been used to measure the 17O/16O ratio of CO2 gas. They …


Observational Constraints On The 520 Km Mantle Discontinuity, Mantle Transition Zone Anisotropy, And Local Seismicity At Mount St. Helens, Han Zhang Jun 2022

Observational Constraints On The 520 Km Mantle Discontinuity, Mantle Transition Zone Anisotropy, And Local Seismicity At Mount St. Helens, Han Zhang

Earth and Planetary Sciences ETDs

Seismology provides valuable observational constraints to thermal and compositional states at inaccessible depths via understanding how elastic wave propagating through them. While many of fundament questions regarding solid Earth structures have been addressed during its more than 100 years history, some details remain unfilled and carefully designed approaches are needed to complete the pictures. This dissertation contributes observational constraints on three topics with newly developed methods. 1) We detected a controversial mantle discontinuity at about 520 km and concluded a mean mantle composition close to the Pyrolite model based on its seismic properties. 2) We isolated anisotropic effects in mantle …


Tree Ring Isotopic Reconstruction Of Hurricane Dolores, Jonathan Kane Jun 2022

Tree Ring Isotopic Reconstruction Of Hurricane Dolores, Jonathan Kane

Earth and Planetary Sciences ETDs

Tree rings contain high-resolution climate proxies of temperature and precipitation (Hughes et al., 1982; Fritts 2012; Scuderi 1993). The objective of this study was to use tree ring cellulose, specifically measuring δ18O - the oxygen-18 to oxygen-16 stable isotope ratio- to investigate the impact of Hurricane Dolores, a tropical cyclone that produced heavy precipitation in the Sierra Nevada in July 2015. Prior studies (Berkelhammer and Stott, 2008, 2009) have shown that conifer forests in California record the influence of varying precipitation regimes in their ring alpha-cellulose. Hurricane Dolores produced an intense precipitation event that inundated parts of the Mojave Desert …


Using Triple Oxygen Isotopes To Reveal The Origin And Evolution Of Mantle Eclogite, Catherine Mary Peshek Jan 2022

Using Triple Oxygen Isotopes To Reveal The Origin And Evolution Of Mantle Eclogite, Catherine Mary Peshek

Earth and Planetary Sciences ETDs

Triple oxygen isotope (TOI) measurements of mantle eclogite from the Orapa kimberlite pipe have reconstructed bulk rock '18O values from 4.587 to 9.542‰ (vs. VSMOW) and '17O from -0.075 to -0.044‰ (vs. VSMOW,  ~0.528). TOI values show increasing '18O with decreasing '17O, overlapping with modern measured altered oceanic crust. Orapa eclogite xenoliths with alkali enrichments show variable mantle-like and heavy 18O, consistent with subduction of seafloor altered basalt. Na# (Na/Na+Ca) in clinopyroxene for some xenoliths pairs with mantle-like oxygen, variable and extreme LREE enrichment, elevated Mg# and lower jadeite contents. These samples preserve records of eclogite melting, mantle interaction …


Geochemical And Sensor-Based Monitoring Of Fault-Associated Carbonic Springs In Grand Canyon And Northern New Mexico: Identifying Hydrologic Pathways And Establishing Baselines, Chris Mcgibbon Dec 2021

Geochemical And Sensor-Based Monitoring Of Fault-Associated Carbonic Springs In Grand Canyon And Northern New Mexico: Identifying Hydrologic Pathways And Establishing Baselines, Chris Mcgibbon

Earth and Planetary Sciences ETDs

This dissertation examines the interaction of spring systems and faulting. When springs discharge within a fault zone the interaction is often complex, and multiple methods are required to understand the flow, mixing and evolution of groundwater. In karst aquifer systems fracture networks can range from sub-millimeter to meters and only adds to the complexities involved in examining spring hydrology. The Interest in springs and faulting is not only driven by science, but also has applied applications. Faulting and fluid flow are of interest to the oil and gas industry, and potential CO2 sequestration. In the southwestern US, water quantity …


The Birth And Incision History Of The San Juan River In The Past 5 Ma, Micael T. Albonico Nov 2021

The Birth And Incision History Of The San Juan River In The Past 5 Ma, Micael T. Albonico

Earth and Planetary Sciences ETDs

This study addresses the evolution of the San Juan River system and its confluence with the Colorado River, ~ 100 km above the regionally important Lees Ferry knickzone. The San Juan River is a 600-km-long continental-scale tributary of the Colorado River. From its headwaters in the San Juan Mountains in Colorado, the San Juan River flows across the Colorado Plateau, and into the Colorado River upstream of Grand Canyon. Published apatite fission track and apatite (U-Th)/He thermochronologic data show that rocks in Marble Canyon, as well as in middle and upper reaches of the San Juan River, were >75 °C …


The Morphology And Evolution Of Transverse Aeolian Ridges On Mars, Timothy Paul Nagle-Mcnaughton Oct 2021

The Morphology And Evolution Of Transverse Aeolian Ridges On Mars, Timothy Paul Nagle-Mcnaughton

Earth and Planetary Sciences ETDs

Transverse aeolian ridges (TARs) are enigmatic and largely relict bedforms on the surface of Mars. TARs are sparsely distributed but common on Mars, but their history, preservation, and past role in the sediment cycle is not well understood. First described in 2003, and detailed extensively in 2008, our study of TARs has been narrowly focused in the last decade, with more and more research noting their presence, but little investigation of the features themselves. Recent work has mostly focused on identifying Terran analogues for TARs, but TARs remain largely a unique Martian feature. In this manuscript, I clarify and refine …


Single-Crystal Elasticity Of Tremolite At High-Pressure Conditions And Its Implication For The Mid-Lithospheric Discontinuity, Soisiri Charin Jul 2021

Single-Crystal Elasticity Of Tremolite At High-Pressure Conditions And Its Implication For The Mid-Lithospheric Discontinuity, Soisiri Charin

Earth and Planetary Sciences ETDs

Tremolite is the calcium magnesium amphibole that widely occurs in igneous and metamorphic rocks of the crustal and upper mantle lithosphere, especially in the greenschist facies to amphibolite facies of ultramafic assemblages. The stability field of amphibole reaches 3-4 GPa and 1100-1200°C depending on water content and cation substitutions giving rise to amphibole to occur in highly variable compositions. This P-T condition, corresponding to the depth about 80-120 km, coincides with the depth range that a negative velocity gradient usually found within most stable cratonic lithospheres. This depth range is seismically called Mid-lithosphere discontinuity (MLD). The geologic processes that might …


Petrology And Geochemistry Of Evolved Achondrites: Planetesimal Mantles And Crusts, Zoltan Vaci Jul 2021

Petrology And Geochemistry Of Evolved Achondrites: Planetesimal Mantles And Crusts, Zoltan Vaci

Earth and Planetary Sciences ETDs

Melting and differentiation are fundamental to early solar system evolution on planetary bodies that accreted enough material to heat up radioactively or through impacts and breach their solidi. Partially and fully melted material is present in the meteorite record in the form of primitive achondrites and achondrites, which are fragments of planetesimals that underwent heating events in the first few million years of solar system history. Although the vast majority of this material is mafic or ultramafic, new evolved samples, recovered in the last few decades, are pushing the petrologic and geochemical boundaries of planetesimal melting, differentiation, and crust formation. …


Investigations Of Geochemical Variations With Depth At The First 15 Drill Sites On Mars Analyzed By The Chemcam Instrument Onboard The Curiosity Rover And Supported By Laboratory Studies And Analog Research At The Valle Grande Paleolake, Valles Caldera, New Mexico, Usa, Ryan S. Jackson May 2021

Investigations Of Geochemical Variations With Depth At The First 15 Drill Sites On Mars Analyzed By The Chemcam Instrument Onboard The Curiosity Rover And Supported By Laboratory Studies And Analog Research At The Valle Grande Paleolake, Valles Caldera, New Mexico, Usa, Ryan S. Jackson

Earth and Planetary Sciences ETDs

The ChemCam instrument collected a wealth of data during the first 15 drill campaigns and on the distribution of trace elements at Yellowknife Bay, Mars. The drill sites investigation showed that most sites were geochemically homogenous down the depth of the drill hole. Two sites in the Stimson formation contained a vertical gradient of decreasing silica down > 3 cm. This gradient may be the result of groundwater flow and is likely recent, within 2.3 Ma. The trace element research was grounded with an analog study at the Valle Grande paleolake in New Mexico. We observed progressive alteration in the minerology …


A Triple Oxygen Isotope Analysis Of Altered Oceanic Crust And Its Buffering Effect On The Steady State Oxygen Isotope Composition Of Seawater, Jesse P. Mcgunnigle May 2021

A Triple Oxygen Isotope Analysis Of Altered Oceanic Crust And Its Buffering Effect On The Steady State Oxygen Isotope Composition Of Seawater, Jesse P. Mcgunnigle

Earth and Planetary Sciences ETDs

The secular chemical marine sediment trend showing an increase in δ18O over geologic time has traditionally been investigated using δ18O modelling of ancient ocean compositions, ocean surface temperatures, and sample diagenetic alteration. This study presents a triple oxygen isotope mass balance for the oceans using high precision δ18O and Δ'17O measurements of altered oceanic crust. The mass balance model predicts an ice-free seawater with δ18O = -0.29‰ and Δ’17O = -0.002‰ with steady state reached at approximately (0.5 to 1)×109 years. Modifications to the hydrothermal alteration and …


Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi Apr 2021

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi

Earth and Planetary Sciences ETDs

Multiple linear regression was used to determine the relationships between diversity-independent factors (i.e., abiotic, climatic) 2, 5, and 10 Myrs-prior to the most elevated Phanerozoic extinctions. We constructed five abiotic variables from Phanerozoic proxy records1–5 to compare to extinction rates: mean temperature, temperature instability, carbon cycle instability, continental weathering rates, and habitat instability. All three models were statistically significant (P < 0.05) and explained > 70% of the variation in Alroy’s6 three-timer generic extinction rates. However, the 2 Myr-prior model explained the most variance in extinction rates and had the most predictive power, based on adjusted and predictive R2 (~ 72% and 41%, respectively). Carbon …


Microstructural Constraints On The Nebular And Asteroidal Histories Of Calcium-Aluminum-Rich Inclusions From Cv3 Chondrites, Shaofan Che Dec 2020

Microstructural Constraints On The Nebular And Asteroidal Histories Of Calcium-Aluminum-Rich Inclusions From Cv3 Chondrites, Shaofan Che

Earth and Planetary Sciences ETDs

The petrology and mineralogy of calcium-aluminum-rich inclusions (CAIs) from CV3 carbonaceous chondrites have been investigated using transmission electron microscopy (TEM). The goal of this dissertation is twofold: (1) to gain new insights into the nebular processes, such as vapor-solid reactions, accretion, transport, that are responsible for the formation of non-igneous CAIs, and (2) to better understand the role of fluid in the secondary alteration of CAIs on the CV3 chondrite parent body. This work represents the first systematic microstructural study of CAIs from CV3 chondrites.

Chapter 2 presents the microstructural observations of primary mineralogies of fine-grained, spinel-rich inclusions (FGIs) from …


Boron Adsorption In Clay Minerals: Implications For Martian Groundwater Chemistry And Prebiotic Processes, Matthew A. Nellessen, Laura Crossey, Patrick J. Gasda, Horton Newsom, Abdulmehdi Ali, Eric J. Peterson, Nina Lanza, Adriana Reyes-Newell, Dorothea Delapp, Chris Yeager, Andrea Labouriau, Roger C. Wiens, Samuel Clegg, Shelbie Legett, Debarati Das Nov 2020

Boron Adsorption In Clay Minerals: Implications For Martian Groundwater Chemistry And Prebiotic Processes, Matthew A. Nellessen, Laura Crossey, Patrick J. Gasda, Horton Newsom, Abdulmehdi Ali, Eric J. Peterson, Nina Lanza, Adriana Reyes-Newell, Dorothea Delapp, Chris Yeager, Andrea Labouriau, Roger C. Wiens, Samuel Clegg, Shelbie Legett, Debarati Das

Earth and Planetary Sciences ETDs

Boron has been detected on Mars [Gasda et al., 2017, Das et al., 2019, 2020] within calciumsulfate veins found within clay-rich rocks on Mars by the Mars Science Laboratory (MSL) rover using Laser Induced Breakdown Spectroscopy (LIBS) analysis. Boron plays a vital role in stabilizing ribose on Earth and has been suggested as a key requirement for life [Scorei et al., 2006, 2012; Furukawa et al., 2013, 2017; Becker et al., 2019]. Additionally, boron readily adsorbs to phyllosilicate clay minerals and is often associated with biologic processes in clay soils. The discovery of boron on Mars in proximity to phyllosilicate …


Quaternary Shelf-Slope Development In The Northern Gulf Of Alaska From Combined Geophysical And Geomorphologic Analysis, Wesley A. Clary Jul 2020

Quaternary Shelf-Slope Development In The Northern Gulf Of Alaska From Combined Geophysical And Geomorphologic Analysis, Wesley A. Clary

Earth and Planetary Sciences ETDs

This dissertation follows the hybrid format as defined by the Office of Graduate Studies at the University of New Mexico. The three chapters defined herein were prepared as manuscripts to be submitted for publication in peer reviewed journals in the field of Earth sciences. A version of chapter 1 was published in Proceedings of the Integrated Ocean Drilling Program, 2017, Volume 41. Chapter 2 was submitted to Marine Geology in Feb 2020, and is under revision as of this date. A version of chapter 3 will be submitted to the Journal of Geophysical Research. In chapter 1, I …


Fluvial Geomorphic And Hydrologic Evolution And Climate Change Resilience In Young Volcanic Landscapes: Rhyolite Plateau And Lamar Valley, Yellowstone National Park, Benjamin Newell Burnett Jul 2020

Fluvial Geomorphic And Hydrologic Evolution And Climate Change Resilience In Young Volcanic Landscapes: Rhyolite Plateau And Lamar Valley, Yellowstone National Park, Benjamin Newell Burnett

Earth and Planetary Sciences ETDs

Quaternary volcanism associated with the last caldera cycle in Yellowstone National Park included emplacement of ash-flow tuffs, massive rhyolite flows ranging from 79 to 484 ka, and valley-filling basalts. This study examines (1) the evolution of spring hydrology with flow age on the Rhyolite Plateau, (2) initial development and evolution of stream networks on the rhyolite flows, and (3) the impact of the 630 ka caldera formation and volcanic flow emplacement on Lamar Valley incision rates.

Integrated stream networks formed within 79 kyr on the Rhyolite Plateau. Incision is focused on steep flow margins and knickpoints and is dependent on …


Triple Oxygen Isotope Composition Of Carbonates, Jordan A.G. Wostbrock Jul 2020

Triple Oxygen Isotope Composition Of Carbonates, Jordan A.G. Wostbrock

Earth and Planetary Sciences ETDs

This dissertation presents a method of analyzing the triple oxygen isotope compositions of carbonates, presents an empirical calibration of the carbonate-water equilibrium fractionation line, presents a triple oxygen isotope equipped fluid-rock mixing model for carbonates to see-through diagenesis, and applies all these findings to ancient carbonate samples. Using modern carbonates and associate water, the following equations are calculated to describe equilibrium triple oxygen isotope fractionation of carbonates:

1000lnalpha18Occ-wt=2.84x106/T2-2.96 1),

Thetacc-wt=-1.39/T+0.5305 2).

Using these fractionation equations provides an extremely useful tool to determine whether a carbonate sample is altered or preserves …


Neogene Drainage Reversal And Colorado Plateau Uplift In The Salt River Area, Jordan Curtis Anderson Jul 2020

Neogene Drainage Reversal And Colorado Plateau Uplift In The Salt River Area, Jordan Curtis Anderson

Earth and Planetary Sciences ETDs

The modern Salt River flows southwest from the Colorado Plateau, through the Arizona Transition Zone and into to the Basin and Range. Rivers in this area flowed northeast during the Paleogene from the Laramide Mogollon Highlands into structural basins of the topographically lower southern Colorado Plateau area. One of these rivers carved the Salt River paleocanyon through a portion of the Mogollon Highlands known as the Apache Uplift to similar depths as the modern Grand Canyon. This study refines the timing of this drainage reversal in the Salt River area by constraining the ages of paleoriver sediments deposited during the …


Integrated Studies Of Intracontinental Deformation In The Interior Western Usa, Cretaceous To Recent, Jacob Oliver Thacker May 2020

Integrated Studies Of Intracontinental Deformation In The Interior Western Usa, Cretaceous To Recent, Jacob Oliver Thacker

Earth and Planetary Sciences ETDs

The advent of plate tectonic theory satisfactorily explained a number of deformation belts around the world. However intracontinental deformation (deformation inboard of a plate margin) remains poorly understood in plate tectonic models. In order to further our understanding of intracontinental tectonics and its effects, this dissertation examines paleotectonic and neotectonic settings within the interior western USA.

Chapter 1 focuses on late Miocene–Recent deformation inboard of the San Andreas plate margin fault and its role on the integration history of the lower Colorado River. The neotectonic analysis included geometric and kinematic fault data collected in key geologic units to characterize the …


Structural And Geochronologic Constraints On The Duration Of The Picuris Orogeny And Demise Of An Orogenic Plateau, Northern Nm, Daniel J. Young Dec 2019

Structural And Geochronologic Constraints On The Duration Of The Picuris Orogeny And Demise Of An Orogenic Plateau, Northern Nm, Daniel J. Young

Earth and Planetary Sciences ETDs

Metasedimentary and igneous basement rocks in northern New Mexico record episodic pulses of tectonism during cratonic growth from 1.8 to 1.38 Ga. Continued challenges involve parsing the deformational features attributable to the Yavapai Orogeny (1.71-1.68 Ga), Mazatzal orogeny (1.66-1.60 Ga), and Picuris orogeny (1.5-1.38 Ga) in this region and understanding how older structures may have been overprinted and reactivated to explain the observed strain. This paper presents regional cross-sections of the 1.7 Ga Vadito, 1.68 to 1.50 Ga Hondo, and 1.5-1.45 Ga Trampas groups of the Picuris Mountains and Rio Mora areas of northern New Mexico combined with new geochronologic …