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Full-Text Articles in Physical Sciences and Mathematics

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 …


Landscape Evolution Of The Southern Colorado Plateau Using Low-Temperature Apatite Thermochronology And Detrital Zircon And Sanidine Provenance Studies, Carmen L. Winn Dec 2019

Landscape Evolution Of The Southern Colorado Plateau Using Low-Temperature Apatite Thermochronology And Detrital Zircon And Sanidine Provenance Studies, Carmen L. Winn

Earth and Planetary Sciences ETDs

Chapter 1: Westernmost Grand Canyon

Conflicting hypotheses about the timing of carving of the Grand Canyon involve either a 70 Ma (“old”) or < 6 Ma (“young”) Grand Canyon. This paper evaluates the controversial westernmost segment of the Grand Canyon where the following lines of published evidence firmly favor a “young” Canyon. 1) North-derived Paleocene Hindu Fanglomerate was deposited across the present track of the westernmost Grand Canyon, which therefore was not present at ~55 Ma. 2) The 19 Ma Separation Point basalt is stranded between high relief side canyons feeding the main stem of the Colorado River and was emplaced before these tributaries and the main canyon were incised. 3) Geomorphic constraints indicate that relief generation in tributaries and on plateaus adjacent to the westernmost Grand Canyon took place after 17 Ma. 4) The late Miocene-Pliocene Muddy Creek Formation constraint shows that no river carrying far-traveled materials exited at the mouth of the Grand Canyon until after 6 Ma.

Interpretations of previously-published low-temperature thermochronologic data conflict with these lines of evidence, but are reconciled in this paper via the integration of three methods of analyses on the same sample: apatite (U-Th)/He ages (AHe), 4He/3He thermochronometry (4He/3He), and apatite fission-track ages and lengths (AFT). “HeFTy” software was used to generate time-temperature (t-T) paths that predict all new and published 4He/3He, AH, and AFT data to within assumed …


Using Archaeological Remote Sensing To Evaluate Land Use And Constructed Space In Chaco Canyon, Jennie O. Sturm Dec 2019

Using Archaeological Remote Sensing To Evaluate Land Use And Constructed Space In Chaco Canyon, Jennie O. Sturm

Anthropology ETDs

Archaeological remote sensing includes a suite of non-invasive methods that can be used to study elements of the archaeological record that may not be achievable otherwise. Using primarily geophysical remote sensing, and especially ground-penetrating radar (GPR), three studies involving questions of “use” were conducted in Chaco Canyon, New Mexico. The first used GPR to study the built interior features of a single room in Pueblo Bonito to evaluate use and function of that room. Three categories of features were identified in the GPR data and confirmed with subsequent excavation. The second study used GPR to re-evaluate an enigmatic land use …


Basal Travertine Of The Bouse Formation: Geochemistry, Diagenesis And Implications For The Integration Of The Colorado River, Christina Ferguson Dec 2019

Basal Travertine Of The Bouse Formation: Geochemistry, Diagenesis And Implications For The Integration Of The Colorado River, Christina Ferguson

Earth and Planetary Sciences ETDs

The Pliocene Bouse Formation is discontinuously exposed in the lower Colorado River region and is a record of the first arrival of the Colorado River to the Gulf of California 5 million years ago. It consists broadly of a lower carbonate member (travertine, marl, and bioclastic units) and an upper siliciclastic member (claystone, mudstone, and Colorado River sands). This paper focuses on the basal travertine (synonymous with “tufa”) unit of the lower carbonate member. Because of its basal position and its chemical encrustation of pre-Bouse topography, the travertine can offer insight into the earliest depositional settings and may be a …


Interpreting Amalgamation Processes Of A Fluvial Sandstone Of The Nacimiento Formation In The San Juan Basin, New Mexico, Keely Elizabeth Miltenberger Dec 2019

Interpreting Amalgamation Processes Of A Fluvial Sandstone Of The Nacimiento Formation In The San Juan Basin, New Mexico, Keely Elizabeth Miltenberger

Earth and Planetary Sciences ETDs

Outcrop studies of fluvial sand bodies are important for the study of fluid transport and storage capabilities because the deposits are heterogeneous. 3-D photogrammetry was used to evaluate the amalgamation processes of a multi-storey sheet sandstone in the San Juan Basin, NM. The Angel Peak member was deposited in the proximal-medial transition of a distributive fluvial system by a meandering river during the Paleocene. Within the study area, amalgamation occurred by avulsion and reoccupation of channel-belts to produce five storeys of the multi-storey sheet sandstone. Within each storey is evidence of processes that are internal to a channel-belt, such as …


Reconstructing Energy Flow Through Modern And Historical Marine Communities: Insights From Amino Acid Isotope Analysis, Emma A. Elliott Smith Dec 2019

Reconstructing Energy Flow Through Modern And Historical Marine Communities: Insights From Amino Acid Isotope Analysis, Emma A. Elliott Smith

Biology ETDs

The fundamental currency of life is energy. Organisms need energy to grow, to survive and to reproduce. Understanding the acquisition of energy by consumers is thus a foundational aspect of biological research. This is especially important in the modern era, as impacts of ongoing anthropogenic effects will be mediated or amplified through food webs. Here, I explore how isotopic analysis of individual amino acids – a technique new to ecological studies – can be used to trace energy flow through animal communities in modern and ancient time periods. In particular, I focus on kelp forest food webs, which are nearshore …


Crustal Structure Beneath The East Coast Magnetic Anomaly From Seismic Refraction Tomography, Collin C. Brandl Dec 2019

Crustal Structure Beneath The East Coast Magnetic Anomaly From Seismic Refraction Tomography, Collin C. Brandl

Earth and Planetary Sciences ETDs

Syn-rift igneous addition is necessary for successful continental breakup. Past investigations of passive margins have focused on strike perpendicular structure, but potential field anomalies indicate that significant crustal variations may be present. Data from 21 ocean bottom seismometers was acquired as part of the Eastern North American Margin Community Seismic Experiment and was used for tomographic inversion to create 2D velocity models of the margin that are representative of crustal structure. Crustal thickness varies along-strike from ~20 km to ~24 km and a high velocity (Vp > 7 km/s) layer is present at the base of the crust above the Moho. …


Organic/Inorganic Interfacial Interactions Affecting Metal Reactivity: Water Treatment And Sensor Applications, Mohamed Nabil Shaikh Aug 2019

Organic/Inorganic Interfacial Interactions Affecting Metal Reactivity: Water Treatment And Sensor Applications, Mohamed Nabil Shaikh

Civil Engineering ETDs

The aim of this dissertation was to investigate the interactions occurring at the organic – inorganic interface between solid media and aqueous contaminants for water treatment and sensor applications. The gaps in current literature on these interfacial organic-inorganic interactions must be bridged in order to develop advanced water treatment and monitoring technologies for improving water quality and thus, restore and protect the contaminated water resources. As a part of this dissertation, manganese oxides-based composites and electrospun polymer mats were developed and investigated for gaining mechanistic insights of organic (bisphenol A and acetaminophen) and inorganic (uranium) contaminants removal, respectively. These reactions …


Eutherian Biogeography During The Puercan North American Land Mammal Age (Paleocene, Earliest Danian): Problems And Potential Solutions, Jason Sterling Silviria Jul 2019

Eutherian Biogeography During The Puercan North American Land Mammal Age (Paleocene, Earliest Danian): Problems And Potential Solutions, Jason Sterling Silviria

Earth and Planetary Sciences ETDs

The Puercan North American Land Mammal Age (NALMA) is the earliest major North American terrestrial biochron of the Cenozoic era, spanning roughly the first one million years of the Paleogene period (Paleocene epoch, Danian stage; ~66.04-65.12 Ma). It is typified by the explosive ecomorphological diversification of the mammalian clade Eutheria (particularly our subclade, Placentalia), following the annihilation of non-avian dinosaurs and “archaic” mammal groups during the Cretaceous/Paleogene (K-Pg) mass extinction event. The spatiotemporal mode and tempo of Puercan eutherian diversification has long been the subject of debate, with disagreements over biogeographic zonation. The traditional model – based largely on well-sampled, …


Evaluating Sources Of Hydrochemical Variability And Mixing In The Upper Gila River, New Mexico, Pavel Vakhlamov Jul 2019

Evaluating Sources Of Hydrochemical Variability And Mixing In The Upper Gila River, New Mexico, Pavel Vakhlamov

Earth and Planetary Sciences ETDs

This study of the upper reaches of the Gila River basin in southwestern New Mexico reveals both spatial and seasonal patterns in physical and hydrochemical parameters. Monsoonal precipitation, temporal variability in water chemistry of streams in the upper Gila watershed is significantly impacted by surface runoff due to variability in landscape cover features, as well as surface area of the catchment. However, during base flow regimes spring inputs are the dominant drivers of solute concentrations and chemical variability.

Geothermal sources play a major role in salinization of the southwestern stream systems. Prolonged water/rock interaction combined with high temperature, pressure result …


Constraining The Oxygen Values Of The Late Cretaceous Western Interior Seaway Using Marine Bivalves, Camille H. Dwyer Jul 2019

Constraining The Oxygen Values Of The Late Cretaceous Western Interior Seaway Using Marine Bivalves, Camille H. Dwyer

Earth and Planetary Sciences ETDs

The Western Interior Seaway (WIS) remains an oceanographic enigma, including its circulation, similarity to the open ocean, and the fidelity of geochemical proxies to reconstruct paleoenvironments. Across the late Campanian and early Maastrichtian I test whether: 1) the WIS had unique δ18OVPDB compared to other marine settings, 2) increasing oceanographic restriction changed the stable isotope composition, and 3) biases, e.g., taxonomy or diagenesis, influenced stable isotope compositions. Results indicate distinct δ18OVPDB in the WIS compared to other marine settings. δ18OVPDB values were stable through time, suggesting insignificant oceanographic restriction and a …


Carbon And Nitrogen Stable Isotopes In Organic Matter From Lake Chalco, Mexico: A Record Of Quaternary Hydrology And Climate Change, Kristin Slezak Pearthree Jul 2019

Carbon And Nitrogen Stable Isotopes In Organic Matter From Lake Chalco, Mexico: A Record Of Quaternary Hydrology And Climate Change, Kristin Slezak Pearthree

Earth and Planetary Sciences ETDs

Sediment cores from Lake Chalco, central Mexico, were analyzed to reconstruct paleoclimate in the neotropics. This study employs total organic carbon, organic carbon-organic nitrogen ratios, carbon and nitrogen stable isotope ratios of organic matter (OM), and lithology to reconstruct changes in lake level and productivity. During Marine Isotope Stage 3 (~42-29 ka) bulk OM d13C and d15N results suggest the lake experienced strong evaporation and high pH due to warm temperatures and moderate precipitation. Large amounts of terrestrial C3 plant matter were deposited during the Last Glacial Maximum (~22-19 ka), suggesting a swampy environment resulting from …


Architecture And Evolution Of The Peace Vallis Distributive Fluvial System, Gale Crater, Mars, Zachary E. Gallegos Jul 2019

Architecture And Evolution Of The Peace Vallis Distributive Fluvial System, Gale Crater, Mars, Zachary E. Gallegos

Earth and Planetary Sciences ETDs

The Peace Vallis alluvial fan, located within Gale crater on the planet Mars, is a distributive fluvial system indicating a wet climate in Mars’ past. The Mars Science Laboratory rover instrument ChemCam, with the high-resolution Remote Micro-imager, was utilized to remotely explore the Peace Vallis alluvial fan and surrounding areas area. The Peace Vallis imaging campaigns 1 and 2, led by Dr. Horton Newsom and Zachary Gallegos respectively, acquired 20 distinct rover observations with a total of 243 individual images to investigate the fan. Using visual interpretation of the images and GIS techniques, this study interprets the processes and products …


Natural Salinization Of The Jemez River, New Mexico: An Insight From Trace Element Geochemistry, Jon K. Golla Jul 2019

Natural Salinization Of The Jemez River, New Mexico: An Insight From Trace Element Geochemistry, Jon K. Golla

Earth and Planetary Sciences ETDs

The Jemez River, a tributary of the Rio Grande in north-central New Mexico, receives thermal water input from the geofluids of the Valles Caldera, an active, high-temperature, liquid-dominated geothermal system. We focus on a ∼50-km portion of the northern Jemez River. This research extends previous decadal work (Crossey et al., in prep., 2013) on major chemistry in the river by characterizing the response of 16 trace elements to geochemical contributions from geothermal waters (McCauley, Spence, Soda Dam, and Jemez Springs springs and San Ysidro mineral waters), an area with copious hydrothermal degassing (Hummingbird), and two major tributaries (Rio San Antonio …


An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp Jul 2019

An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp

Earth and Planetary Sciences ETDs

Recent studies have shown water vapor isotopologues to be sensitive tracers of mixing processes that govern low-cloud feedback in climate models. In this study, we develop an inverse model (MBL Mix inverse model) that uses one year of isotope and humidity observations from Graciosa Island, Azores to estimate mixing for four seasons. We show the dry end-member of the model, the lower free troposphere (LFT), can be represented using Rayleigh fractionation. Isotope observations from Graciosa Island are compared to other field locations to discuss controls on isotopic variability other than mixing. Output from the MBL Mix inverse model shows the …


Evaluating Future Reservoir Storage In The Rio Grande Using Normalized Climate Projections And A Water Balance Model, Nolan T. Townsend Jul 2019

Evaluating Future Reservoir Storage In The Rio Grande Using Normalized Climate Projections And A Water Balance Model, Nolan T. Townsend

Earth and Planetary Sciences ETDs

We develop and implement new tools for assessing the future of surface water supplies in downstream reaches of the Rio Grande, for which Elephant Butte Reservoir is the major storage reservoir. First, a normalization procedure is developed to adjust natural Rio Grande streamflows simulated by dynamical models in downstream reaches. The normalization accounts for upstream anthropogenic impairments to flow that are not considered in the model, thereby yielding downstream flows closer to observed values and more appropriate for use in assessments of future flows in downstream reaches. The normalization is applied to assess the potential effects of climate change on …


Early Mississippian Ocean Anoxia Triggering Organic Carbon Burial And Enhancing Late Paleozoic Ice Age Onset: Evidence From Uranium Isotopes Of Marine Limestones, Keyi Cheng Jul 2019

Early Mississippian Ocean Anoxia Triggering Organic Carbon Burial And Enhancing Late Paleozoic Ice Age Onset: Evidence From Uranium Isotopes Of Marine Limestones, Keyi Cheng

Earth and Planetary Sciences ETDs

The Early Mississippian (Tournaisian) positive δ13C excursion (or TICE) is one of the largest recorded in the Phanerozoic and the organic carbon (OC) burial associated with its development is hypothesized to have driven global cooling and increased glaciation. We are testing the hypothesis that expanded ocean euxinia/anoxia drove widespread OC burial and the TICE and we are testing this hypothesis using uranium isotopes (δ238U) of Lower Mississippian marine limestones from southern Nevada as a global seawater redox proxy.

δ238U trends record a prominent mid-Tournaisian negative excursion (~0.30‰ magnitude) lasting ~1 My. The lack of …


An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp Jul 2019

An Estimation Of Lower Tropospheric Mixing Derived From Inverse Modeling Of Boundary Layer Water Vapor Isotopologues On Graciosa Island, Azores, Jacquelyn M. Delp

Earth and Planetary Sciences ETDs

Recent studies have shown water vapor isotopologues to be sensitive tracers of mixing processes that govern low-cloud feedback in climate models. In this study, we develop an inverse model (MBL Mix inverse model) that uses one year of isotope and humidity observations from Graciosa Island, Azores to estimate mixing for four seasons. We show the dry end-member of the model, the lower free troposphere (LFT), can be represented using Rayleigh fractionation. Isotope observations from Graciosa Island are compared to other field locations to discuss controls on isotopic variability other than mixing. Output from the MBL Mix inverse model shows the …


Observed And Projected Snowmelt Runoff In The Upper Rio Grande In A Changing Climate, Nels R. Bjarke Jun 2019

Observed And Projected Snowmelt Runoff In The Upper Rio Grande In A Changing Climate, Nels R. Bjarke

Earth and Planetary Sciences ETDs

As climate has warmed over the past half century, the strength of the covariance between interannual snowpack and streamflow anomalies in the Rio Grande headwaters has decreased. This change has caused an amplification of errors in seasonal streamflow forecasts using traditional statistical forecasting methods, based on the diminishing correlation between peak snow water equivalent (SWE) and subsequent snowmelt runoff. Therefore, at a time when water resources in south-western North America are becoming scarcer, water supply forecasters need to develop prediction schemes that account for the dynamic nature of the relationship between precipitation, temperature, snowpack and streamflow. We quantify temporal changes …


Fluid Transport In Porous Media For Engineering Applications, Eric M. Benner May 2019

Fluid Transport In Porous Media For Engineering Applications, Eric M. Benner

Chemical and Biological Engineering ETDs

This doctoral dissertation presents three topics in modeling fluid transport through porous media used in engineering applications. The results provide insights into the design of fuel cell components, catalyst and drug delivery particles, and aluminum- based materials. Analytical and computational methods are utilized for the modeling of the systems of interest. Theoretical analysis of capillary-driven transport in porous media show that both geometric and evaporation effects significantly change the time dependent behavior of liquid imbibition and give a steady state flux into the medium. The evaporation–capillary number is significant in determining the time-dependent behavior of capillary flows in porous media. …


Irrigation Forbearance In The Middle Rio Grande: Using Remote Sensing To Improve Investments, Trevor Birt Apr 2019

Irrigation Forbearance In The Middle Rio Grande: Using Remote Sensing To Improve Investments, Trevor Birt

Water Resources Professional Project Reports

In extremely dry years when there is a high premium on surface water, irrigation forbearance agreements help water managers maintain riparian health, fish populations, and ensure water delivery to downstream users. In order for these programs to maximize their effectiveness and limit their impact on agricultural communities, water managers should seek the highest return on investment - or the highest amount of water per acre entered into forbearance. This may be accomplished by assessing the water requirements of fields and then grouping by conveyance lateral, to target the highest among them as good forbearance participants. Unfortunately, irrigation measurement in the …


Melt Inclusions And Their Application - New Perspective On The Subsurface Architecture Of Cerro Negro Volcano, Nicaragua, John M. Hamilton Feb 2019

Melt Inclusions And Their Application - New Perspective On The Subsurface Architecture Of Cerro Negro Volcano, Nicaragua, John M. Hamilton

Earth and Planetary Sciences ETDs

Volatiles are the drivers of volcanic eruptions and monitoring and measurement in quiescent times are the key in determining when unrest within a volcanic system is beginning leading to possible cataclysms. Previous studies have focused on direct measurements from volcanic plumes or fumaroles, however, this study proposes the use of melt inclusions from tephra to determine volatile contents from the 1992 eruption of Cerro Negro Volcano, Nicaragua. The analysis of melt inclusions adds a new technique to the volatile analytical toolbox and can help to determine volatile contents from past eruptions and their subsequent evolution within a volcanic system.

Though …


Northeastern China 4.2ka Database, Louis A. Scuderi, Xiaoping Yamg, Samantha Ascoli, Hongwei Li Jan 2019

Northeastern China 4.2ka Database, Louis A. Scuderi, Xiaoping Yamg, Samantha Ascoli, Hongwei Li

Paleoclimate Datasets

The Hunshandake Sandy Lands of northeastern China, currently a semiarid lightly vegetated region, were characterized by perennial lakes and forest stands in the early and middle Holocene. Well-developed dark grassland-type paleosols (mollisols) at the southern edge of the Hunshandake OSL-dated to between 6.93 +0.61 and 4.27 +0.38 ka along with lacustrine sands at higher elevations that date to between 5.7 +0.3 and 5.2 +0.2 ka and thick gray lacustrine sediments suggest a wetter climate. Between 4.2 and 3.8 ka, the region experienced extreme drying that was exacerbated by lake overflow drainage and sapping that depleted the groundwater table. The region …


How To Celebrate 24 New Year's Eves In A Single Year!, Florentin Smarandache Jan 2019

How To Celebrate 24 New Year's Eves In A Single Year!, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

New Year's Eve 2018 reaches me on Jeju Island, South Korea, in the East China Sea. While I had spent New Year's Eve 2017 in Galapagos Islands, in the Pacific. We can celebrate 24 New Year's Eves in a single year, moving to the West – for example in an orbital spacecraft - (in the reverse sense of Earth's rotation around its axis) at a faster angular speed than Earth's rotation, jumping from one time-zone to another, and starting from the International Date Line. { In this paper we are referring to the solar day, hence to the angular speed …