Earth Sciences Commons^™

Magma Mixing At Oldoinyo Lengai: A Mineralogical And Trace Element Analysis Of The 2007-8 Eruption., Nicole Thomas, Tobias P. Fischer Dr., Adrian J. Brearley Dr.

Earth and Planetary Sciences ETDs

Chapter I:

The 2007-8 eruption at Lengai was highly explosive, reaching plinian proportions, and the anhydrous nature of the nephelinite magma at Lengai, does not explain this highly volatile behavior. The increase in volatiles in a low H2O nephelinite magma could occur from decompression melting of magma injection from a deeper source. Two distinct nephelinite compositions were identified in a mineralogical analyses of the ash erupta: a highly evolved nephelinite (OL2), with less than 3% glass from the magma chamber, as indicated by the highly peralkalinic feldspathoid: combeite (Na2Ca2Si3O9), commonly found in Lengai eruptive products (Dawson 1966, 1998), and a …

Investigation Of Molluscan Survivorship Across The Cenomanian-Turonian Boundary Event Using Ecological Niche Modeling, Agathe E. Carrier

Earth and Planetary Sciences ETDs

In the beginning of the Late Cretaceous, the Western Interior Seaway experienced the effects of a global ocean anoxic event (OAE2, or the Bonarelli Event) across the Cenomanian-Turonian (C/T) boundary (~94 Ma). This event resulted in major environmental and biological disturbances creating significant biotic turnover, with recent research suggesting near mass extinction levels in some clades. In this study we utilize a paleobiological application of a modern ecological modeling technique (PaleoENM), to test whether changes in species’ survivorship and distribution patterns across this event relate to changes in their predicted suitable habitat area and abiotic niche dimensions.

Results suggest that …

Birth And Evolution Of The Virgin River: ~1 Km Of Post-5 Ma Uplift Of The Western Colorado Plateau, Cory J. Walk

Earth and Planetary Sciences ETDs

The uplift history of the Colorado Plateau has been debated for over a century with still no unified hypotheses for the cause, timing, and rate of uplift. 40Ar/39Ar dating of semi-continuous basaltic volcanism over the past ~6 Ma within the Virgin River drainage system, southwest Utah and southern Nevada, provides a way to calibrate differential river incision and compare patterns of basaltic migration, mantle velocity structure, channel steepness, lithology, incision history and the birth and evolution of the Virgin River. New detrital sanidine ages constrain the arrival of the Virgin River across the Virgin Mountains to a maximum depositional age …

A Speleothem Record Of Climate Variability In Southwestern North America During Marine Isotope Stage 3, Justin G. Peinado

Earth and Planetary Sciences ETDs

During Marine Isotope Stage 3 (MIS-3) of the last glacial period, there were rapid transitions between warm and cold climates referred to as Dansgaard-Oeschgerr (DO) events. In Southwestern North America (SWNA), two speleothem paleoclimate records document changes in moisture source delivery in response to DO-events during MIS-3, but do not address potential changes in effective moisture for the region. In this study, we introduce a new high-resolution speleothem paleoclimate record from Carlsbad Cavern in the Guadalupe Mountains. The speleothem, sample BC-5, grew continuously from 46-31 kya during the latter half of MIS-3, based on U-Th dating. We also tied stable …

New Geochemical And Isotopic Approaches To Shallow Crust Landform Evolution, David Decker

Earth and Planetary Sciences ETDs

Many researchers have studied the Guadalupe Mountains in detail and starting with King (1948), many of them have speculated about the timing of the uplift of the Guadalupe block. There are several competing hypotheses including Laramide, Basin and Range, and Rio Grande Rifting uplift scenarios. Using uranium-lead dating of scalenohedral spar found in small vug caves throughout the study area, I have dated the episodes of spar formation to two major phases, 36 to 33 Ma and 30 to 27 Ma. These two episodes of spar formation are in good agreement with the time frame of the ignimbrite flare up …

Application Of Ps Scattering Kernels To Imaging The Mantle Transition Zone With Receiver Functions, Han Zhang, Brandon Schmandt

Earth and Planetary Sciences ETDs

Both the thermal structures and the hydrated level of the mantle transition zone are attractive to researchers in solid Earth science fields. Although some aspects of the questions have been answered based on current geophysical observations, a high resolution seismic map of such layer on a continental scale is still valuable for improving our understanding of the lateral variations inside the mantle transition zone. Here we extend a 3D pre-stacking migration method to make it more applicable for imaging the mantle transition zone depths. After the validation of the method with 1D synthetic data, two types of 2D structures are …

Microtextural Studies Of Feldspar In Ordinary Chondrites, Jonathan A. Lewis

Earth and Planetary Sciences ETDs

Ordinary chondrites contain an important record of events that took place during the earliest period of solar system evolution. These include primary processes, such as chondrule formation, and secondary processes, those that affected asteroids after accretion and modified primary components. Secondary processes include aqueous alteration, thermal metamorphism, and shock effects from impact events. Secondary minerals can provide insight into the chemical and physical conditions that affected their parent asteroids. Feldspar is known to be a secondary mineral that crystallized during thermal metamorphism. The goal of this work is to use the formation and evolution of feldspar to elucidate the conditions …

Primary Pristine And Altered Iron Sulfides In Cm And Cr Carbonaceous Chondrites: Insights Into Nebular And Parent Body Processes, Sheryl A. Singerling

Earth and Planetary Sciences ETDs

This work presents our detailed investigation of textures and major, minor, and trace element compositions of iron sulfides in CM and CR carbonaceous chondrites using scanning electron microscopy (SEM), electron probe microanalysis (EPMA), transmission electron microscopy (TEM) from focused ion beam-prepared (FIB) sections, and synchrotron X-ray fluorescence (SXRF) microanalysis. This study represents the first attempt to link micro- to nano-scale textural and chemical characteristics of CM and CR chondrite primary iron sulfides and their alteration products.

The objectives of our studies included determining: 1) if primary sulfides are present in the least-altered CM and CR chondrites, and if so, 2) …

Global Seawater Redox Trends During The Late Devonian Mass Extinction Detected Using U Isotopes Of Marine Carbonates, David Allen White

Earth and Planetary Sciences ETDs

The Late Devonian extinction ranks as one of the ‘big five’ Phanerozoic extinctions affecting up to 80% of marine species and occurred during five distinct pulses spanning /or widespread marine anoxia. We test the marine anoxia hypothesis by analyzing uranium isotopes (δ²³⁸U) across a ~7 My interval of well-dated Upper Devonian marine carbonates from the Devil’s Gate Limestone in Nevada, USA.

The measured δ²³⁸U curve shows no co-variation with local anoxic facies, water-depth dependent facies changes, redox-sensitive metals, TOC, or diagnostic elemental ratios indicating the δ²³⁸U curve was not controlled by local depositional or …

The Encyclopedia Of Neutrosophic Researchers - Vol. 2, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

This is the second volume of the Encyclopedia of Neutrosophic Researchers, edited from materials offered by the authors who responded to my invitation. The introduction contains a short history of neutrosophics, together with links to the main papers and books. The authors who have published neutrosophic papers, books, or defended neutrosophic master theses or PhD dissertations and are not included in the two ENR volumes, are kindly invited to send their self-presentations or their CVs, a photo, and a list of neutrosophic publications to [email protected] and [email protected] to be part of a third volume.

Florentin Smarandache

Geochemistry Of Volatiles Released By Incipient Continental Rifting And Subduction Processes, Hyunwoo Lee

Earth and Planetary Sciences ETDs

Volatiles (N2, CO2, and He) are released by volcanism and hydrothermal activity during continental rifting and subduction processes. Analyses of volatile components have been conducted to obtain gas contents (CO2, SO2, H2S, N2, Ar, He, and so on), stable isotope compositions (δ13C, δ15N, and so on), and noble gas isotopes (3He/4He, 40Ar/36Ar, and so on). This dissertation includes four chapters to report new nitrogen isotope fractionation factors of bubbling gases during gas-water transfer at various water temperatures (Chapter 1), first measurements of massive amounts of CO2 released by incipient continental rifting in the Magadi and Natron Basin, East African Rift …

Observed Changes In Climate And Streamflow In The Upper Rio Grande Basin, Shaleene Chavarria

Earth and Planetary Sciences ETDs

Observed streamflow and climate data are used to test the hypothesis that climate change is already affecting the streamflow volume derived from snow accumulation in ways consistent with climate model-based projections of 21st century streamflow. Annual and monthly changes in streamflow volume and surface climate variables on the upper Rio Grande (URG) near its headwaters in southern Colorado are assessed for water years 1958-2015. Trends in discharge are examined together with variations in snow water equivalent and surface climate variables. Results indicate that temperatures in the basin have increased significantly primarily in the winter and spring seasons, April 1 snow …

Oxygen Isotope Composition Of Water In Martian Meteorites, Oleg Vitalivich Maltsev

Earth and Planetary Sciences ETDs

The oxygen isotope composition of water extracted from Martian meteorites appears not to be in isotopic equilibrium with the silicate portion of the meteorites. This disequilibrium suggests the existence of multiple distinct oxygen isotope reservoirs on planet Mars. Here we present oxygen isotope measurements of waters extracted from Martian shergottites Tissint, Zagami and NWA-7042 and from nakhlite NWA-10153. These waters were extracted by stepwise heating to preserve segregation between low temperature adsorbed waters, intermediate temperature mineral waters and the high temperature mineral structural OH groups. The results of our study, analyzed cooperatively with previous work by Karlsson et al., (1992) …

Comprehensive Silica Removal With Ferric Compounds For Industrial Wastewater Reuse, Ehren D. Baca

Civil Engineering ETDs

Cooling towers, integrated circuit (IC) manufacture and reverse osmosis (RO) generate copious amounts of wastewater high in colloidal and reactive silica inhibiting on-site or synergistic reuse. Silica present in cooling water can reach solubility limits via evaporation and form impervious scale on heat transfer surfaces that decreases efficiency. When water is treated by RO operating at high rejection, silica forms difficult-to-remove scale on the membrane feed side in the form of glassy patches and communities of aggregate particles, inhibiting aspirations for zero liquid discharge. Current methods for silica scale mitigation include abundant dosing with chemical antiscalents or complex operating schemes. …

Modeling Atmosphere-Mountain Interactions: Implications For Stable Isotope-Based Paleoaltimetry, Lauren B. Wheeler

Earth and Planetary Sciences ETDs

The measure of surface uplift can provide an important constraint on the behavior of continental lithosphere and the underlying upper mantle. Isotope-based paleoaltimetry aims to quantitatively estimate the magnitude and timing of surface uplift from records of the isotopic composition of precipitation in order to provide constraints on the tectonic processes driving mountain building. As the surface of a topographic barrier increases in height, along the windward side, δ-values of precipitation should get progressively more negative, and on the leeside, δ-values of precipitation should also get progressively more negative based on the presence and development of a topographically-induced rain shadow. …

Insights On Magmatic Addition Beneath The Mid-Atlantic Coastal Plain From Crustal Seismic Refraction Data, Thomas W. Luckie

Earth and Planetary Sciences ETDs

Magmatic addition can lead to intraplate crustal growth through plume-generated voluminous underplating of mafic material, particularly during early syn-rift processes. In addition, magmatism facilitates crustal growth and rift development by assisting extensional tectonic forces. Therefore, understanding the relationship between magmatism and rifting may help explain both these processes. In the summer of 2015 the GeoPRISMS Eastern North American Margin (ENAM) Community Seismic Experiment collected two margin-dip active source seismic refraction profiles in eastern North Carolina and southeastern Virginia using five onshore explosive shots on a northern profile and six on a southern profile (see figure). Analysis of these data resulted …

Magmatic Hydrothermal Alteration And Secondary Post-Shock Features In Martian Olivine-Phyric Basalt Northwest Africa 10416; Petrology And Geochemistry Of Primitive Achondrite Northwest Africa 11042, Zoltan Vaci

Earth and Planetary Sciences ETDs

The Martian olivine-phyric basalt Northwest Africa (NWA) 10416 contains large olivine xenocrysts whose cores have been stained brown by hydrothermal alteration and whose rims are composed of pristine olivine overgrowths. Microanalysis of these olivine cores reveals various degrees of amorphization, some of which have been overprinted by terrestrial weathering, evident as part of a weathering rind along the exposed surface of the meteorite. Studies of a completely unweathered terrestrial analogue basalt from southern Colorado reveal similar features and indicate that both basalts were altered in a supersolidus magma chamber setting. The alteration features in NWA 10416 thus imply the presence …

Classifying Microseismicty At Mount St. Helens Using A Large-N Array, Margaret E. Glasgow

Earth and Planetary Sciences ETDs

A dense array of ~1,000 continuously recording, short-period geophones was deployed in the summer of 2014 within ~15 km of Mount St. Helens. Two earthquake catalogs created using reverse time imaging and template detection techniques, increase the detection rate and completeness of the earthquake catalog when compared to the permanent network, Pacific Northwest Seismic Network, catalog. An investigation into event type for ~200 of the earthquake detections leads to the discrimination of two major classification groups, volcano-tectonic and long period. Previous to this study, long period earthquakes had not been identified in the upper crust during a volcanically inactive period …

A Multi-Proxy Stalagmite Reconstruction Of The Climate Of Southwestern North America From The Middle To Late Holocene, Christine Allen

Earth and Planetary Sciences ETDs

The seasonal balance of moisture has a significant effect on natural ecosystems and culture in southwestern North America (SWNA), and it thus is necessary to understand the cause of this moisture variability in order to better predict the scope of potential future changes. Studies of modern SWNA climate indicate that most of the annual moisture at this site comes from monsoonal summer precipitation and a lesser amount of Pacific winter moisture. The climate of the Holocene is of particular interest for constraining natural variability of interglacial climates prior to any anthropogenic influence. An overall transition to a wetter Late Holocene …

The Dynamic Geomorphic Setting Of The Late Pleistocene Hartley Mammoth Site: Burial And Skeletal Preservation In A Slump-Block Depression Near Abiquiu, New Mexico, Jennifer K. Muus

Earth and Planetary Sciences ETDs

Near Abiquiu in northern New Mexico, the skeletal remains of two mammoths were discovered in the summer of 2014 in the near-surface deposits of a very small alluvial channel. The channel occupies a depression on the backtilted top of a Toreva slump block, a highly unusual setting for a mammoth burial. Geomorphological investigation of the site has provided insight into processes leading to burial and preservation of the remains, as well as local environmental change. Field mapping of sediment sources and LiDAR scans of the contributing slope basin and slump bench provided a map of geomorphic features and surficial geologic …

Principles Of Stable Isotope Geochemistry, 2nd Edition, Zachary Sharp

Open Textbooks

Principles of Stable Isotope Geochemistry is written as a textbook to accompany a one semester course in Stable Isotope Geochemistry. There are 13 chapters, each dealing with a specific subtopic of the field. Other than Chapters 1 and 2 – introduction and definitions – most of the remaining chapters can be read without reliance on the preceding ones. It is also hoped that the book will serve as a general reference volume for researchers in the field.

Principles of Stable Isotope Geochemistry has been organized in such a way that major concepts are explained and accompanied by numerous examples. In …

Archived Rock Samples From Jane Selverstone's Research Collection, Jane Selverstone

Earth and Planetary Sciences Faculty and Staff Publications

This Excel spreadsheet lists all of the rock samples from Jane Selverstone's research collection that have been archived into the Earth and Planetary Sciences Collections at the University of New Mexico. All samples are listed by original (published) sample number and by an affiliated International GeoSample Number. Samples are grouped by research project, and doi information is given for all publications resulting from work on each project. Rock samples include various combinations of hand specimens, powders, thin sections, and billets from which thin sections were prepared. Information is included to identify the drawers within which each sample can be found …

New Insights Into The Martian Crust And Angrite Parent Body Through Meteorites, Alison R. Santos

Earth and Planetary Sciences ETDs

Petrologic studies of two new, unique meteorites were conducted in order to characterize the samples and provide insights into their parent bodies. The first sample, Northwest Africa 7034, is the first martian meteorite breccia to be discovered. In an effort to understand the martian crustal materials sampled by the breccia, we developed a classification scheme for the breccia clasts based on their texture, mineralogy, and chemistry. We then further investigated two clast groups which contained trends in mineralogy and chemistry that suggested a possible genetic relationship between the two. Our findings suggest they are not related by a simple igneous …

Abrupt Ocean Anoxia During The Late Ordovician Mass Extinction Detected Using Uranium Isotopes Of Marine Carbonates, Rickey Bartlett, Maya Elrick, Yemane Asmerom, Viorel Atudorei

Earth and Planetary Sciences ETDs

The Ordovician witnessed an explosion in marine biodiversity punctuated by the first of the ‘big-5’ Phanerozoic mass extinctions, the Late Ordovician mass extinction (LOME). The LOME consists of two discrete pulses occurring at the beginning and end of the Hirnantian. Lithologic and geochemical evidence suggests widespread marine anoxia triggered the second LOME pulse; however, most of these redox proxies record local bottom water or porewater conditions rather than global seawater conditions. To evaluate global redox trends, we utilize uranium (U) isotopes and trace element geochemistry of marine carbonates as a global marine redox proxy.

Bulk carbonate samples were collected from …

Birth And Evolution Of The Rio Grande Fluvial System In The Last 8 Ma:Progressive Downward Integration And Interplay Between Tectonics, Volcanism, Climate, And River Evolution, Marisa N. Repasch

Earth and Planetary Sciences ETDs

The Rio Grande-Rio Chama (RG-RC) fluvial system has evolved dramatically over the last 8 Ma, undergoing channel migrations, drainage capture and integration events, volcanic damming, and carving and refilling of paleocanyons. Volcanism concurrent with the development of the river system provides a unique opportunity to apply multiple geochronometers to the study of its incision and drainage evolution. This paper reports 19 new ⁴⁰Ar/³⁹Ar basalt ages and 19 detrital mineral samples (zircon and sanidine) collected from RG-RC alluvium overlain by dated basalt flows in the context of a compilation of published ⁴⁰Ar/³⁹Ar basalt ages. The …

Cl In The Early Solar System, Jeffrey Williams

Earth and Planetary Sciences ETDs

The early solar nebula is thought to have been a turbulent disk of dust and gas. An unknown mechanism caused the disk to collapse, such as a nearby super nova. This collapse led to high temperatures and high particle densities at the mid-plane of the disk. An unknown mechanism caused the temperature in local area to become hot enough to cause some material to melt –creating the first igneous material of the solar system. These melt spherules, called chondrules, cooled and accreted together with dust and ice to form larger bodies called chondrites. Once the chondritic bodies were of sufficient …

Modeling The Influence Of The Heterogeneous Substrate On The Transport Of The Jet Fuel Solute Plume, Kirtland Air Force Base, Albuquerque, New Mexico, Hannah Sarah Gatz-Miller

Earth and Planetary Sciences ETDs

A subsurface model was developed to characterize the influence of heterogeneity on solute phase plume migration of the Jet Fuel spill of Kirtland Air Force Base. Core –logs from KAFB boreholes were compiled, and lithology was interpolated across the study area using transition probability geostatistics (T-PROGS). High conductivity materials in the travel path resulted in a faster than average breakthrough time while, if low conductivity materials were placed in the travel path, particles were either forced to divert around the low K material, which added time and changed the direction of travel, or were forced by the hydraulic gradient to …

Neotectonic Evolution Of Grand Canyon : Interaction Between Volcanism, River Incision, Epeirogenic Uplift, And Faulting, Ryan Crow

Earth and Planetary Sciences ETDs

This thesis focuses on the effects of volcanism, river incision, epeirogenic uplift, and faulting on the landscape evolution of the Grand Canyon region. In the first chapter the migration of increasingly asthenospheric basaltic volcanism is used to constrain lithospheric modification of the Colorado Plateau margins. Buoyancy modification of the upper mantle, driven by the upwelling, is a likely driver for recent uplift of the area. In the second chapter, correlation between oversteepened rivers and areas of high-velocity upper mantle is used to show that recent and ongoing mantle-driven uplift is modulating the surface along the western margin of the Colorado …

Soil Geomorphology Of The Eastern Sevilleta Long Term Ecological Research Site, Debra Bryan-Ricketts

Earth and Planetary Sciences ETDs

Soils in the arid to semi-arid piedmont landscapes of central New Mexico were examined in order to evaluate surficial processes and landscape evolution in the central Rio Grande Rift. These soils were found to contain key information regarding pedologic and geomorphic responses to climate change, rifting and base level drop. A rare association of sepiolite and palygorskite occurs in old soils formed in eolian fines. Pedologic and mineralogical data indicate that palygorskite formed by transformation of dust-borne, aluminum-rich minerals, and that sepiolite subsequently formed by transformation of palygorskite. The association of these two minerals, and geomorphic observations, confirm the existence …

Preparing Water Users In The Lower Rio Grande For Adjudication Through An Informative Workshop, Leslie R. Kryder

Water Resources Professional Project Reports

The Lower Rio Grande basin in New Mexico is currently undergoing water right adjudication. The adjudication process is important to identify and quantify water uses throughout the Lower Rio Grande. It is intended to facilitate water rights administration by the Office of the State Engineer. Where water users do not understand the purpose and process, they may not participate effectively. Through conversations with irrigators and others familiar with the situation, I explore some of the water users perspectives regarding the adjudication. In general, the water users find the adjudication packets received from the Office of the State Engineer difficult to …