Mineral Physics Commons^™

An Investigation Into Transitions In Clay Mineral Chemistry On Mars, Seth Gainey

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is comprised of three studies investigating clay mineralogy on, or near the martian surface, with an introductory chapter, introducing and linking the three studies. Chapter two is on the subject of clay mineral synthesis, including Fe/Mg clay minerals which have been detected at multiple locations across the southern highlands. These Fe/Mg clay minerals have been previously interpreted as forming in anoxic/reducing environments, conducive to the preservation of organic matter. The results of this study suggest that the previous interpretation of Fe/Mg-rich clay as requiring anoxic/reducing conditions may not be accurate, as the minor presence of Mg (below what …

Anomalous Thermal Indicators From Authigenic Minerals In Upper Paleozoic Strata Of The Michigan Basin, Kyle Cox

Masters Theses

Indications of anomalous paleo-temperatures exist in strata of the Michigan basin, USA. The thermal history of the basin was investigated through identification and analysis of authigenic components in two Upper Paleozoic strata, the Devonian Dundee Formation and Mississippian Marshall Sandstone. Formation conditions for diagenetic phases in both units were estimated through a variety of means and compared to conditions expected for a simple burial model. Authigenic clays identified in the Marshall via X-ray diffraction are expected to have formed at temperatures above what would have been produced by burial alone. Stable isotope and fluid inclusion analysis indicate the same for …

Holocene Sedimentology And Stratigraphy Of Coastal Sediments In An Arid Climate, Al Qahmah, Southern Red Sea, Saudi Arabia, Abdullah Ibrahim Nabhan

Doctoral Dissertations

"Holocene sedimentary deposits in Al Qahmah coast, southern Red Sea, in Saudi Arabia have been accumulated on an arid siliciclastic coast in a rift tectonic setting. This study provides a detail interpretation and analysis of sedimentary facies, stratigraphy, depositional environment, and major geological processes. Two studies have been undertaken. First, petrological study of composition and texture of modern sediments and facies mapping delineate facies distribution and mechanisms of sediment transport and deposition. A unique suite of complex riverine, wave, tidal, wind, and chemical and biological processes affect the composition, texture, and distribution of the facies. Second, the depositional environments of …

Ore Classification And Breccia Formation In The 144 Zone Gold Deposit: A Chemical Replacement Model, Bare Mountain Range, Nevada, William Thomas Fischer

UNLV Theses, Dissertations, Professional Papers, and Capstones

The 144 Zone is an oxidized, breccia-hosted, disseminated gold deposit that formed along the contact between Early Cambrian Carrara Formation limestone and overlying Bonanza King Formation dolomite within the Bare Mountain range in southern Nevada. Gold mineralization occurs within a breccia body that contains a variety of breccia types. Research goals of this project included classifying clay, oxide and other minerals as well as breccia types to identify the habits of gold mineralization and the minerals associated with gold. Research was also aimed at determining the paragenesis of Au mineralization and brecciation in the 144 Zone. Underground mapping provided spatial …

Microstratigraphic Logging Of Calcite Fabrics In Speleothems As Tool For Palaeoclimate Studies, Silvia Frisia

International Journal of Speleology

The systematic documentation of calcite fabrics in stalagmites and flowstones provides robustness to palaeoclimate interpretation based on geochemical proxies, but it has been neglected because it is difficult to transform crystal morphologies into numerical values, and construct fabric time series. Here, general criteria that allow for coding fabrics of calcite composing stalagmites and flowstones is provided. Being based on known models of fabric development, the coding ascribes sequential numbers to each fabric, which reflect climate-related parameters, such as changes in drip rate variability, bio-mediation or diagenetic modifications. Acronyms are proposed for Columnar types, Dendritic, Micrite, Microsparite and Mosaic fabrics, whose …

Remote Exploration: Understanding Martian Surface Processes, Sarah M. Bass, Virginia C. Gulick, Natalie Glines, Patrick Freeman

STAR Program Research Presentations

Earth and Mars share many similar physical features, including canyons, valleys, craters, volcanoes, ice, and gullies. My research focuses on two distinct projects. The first concentrates on the formation of gullies, which are channel networks generally formed on mid-latitude crater walls on Mars. Debated gully-forming processes include the melting of snowpacks, sublimation of accumulated carbon dioxide frost, melting of snow-rich dusty mantle material, and groundwater flows. Using High Resolution Imaging Science Experiment (HiRISE) images of gullies and working with Digital Elevation Models (DEMs) in ENVI, we are able to perform detailed studies of gully morphology, including volume calculations using slope, …

Exploring The Link Between Otolith Growth And Function Along The Biological Continuum In The Context Of Ocean Acidification, Eric D. Wilcox Freeburg

Graduate Doctoral Dissertations

Oceans are acidifying as atmospheric CO₂ is drawn down. This process, known as ocean acidification (OA), is well known and documented. Over the next 100 years, pH of the surface ocean is projected to decrease by up to 0.35 units. This CO₂ draw down has a direct effect on dissolved inorganic carbon (DIC) balance in the ocean. OA is expected to impact calcifying organisms that rely on constituencies of the DIC system, specifically carbonate ion [CO₃2-]. It is clear that externally calcified structures, such as coral skeletons, bivalve shells, etc., will be significantly affected as pH, …

The Effect Of Single Crystal Elastic And Plastic Anisotropy On Stress And Strain Heterogeneity: Comparison Of Olivine To Other Common Minerals, Christopher Joseph Cline Ii

UNLV Theses, Dissertations, Professional Papers, and Capstones

In order to investigate the influence of single crystal elastic anisotropy on the heterogeneity of stress distributions during polycrystalline deformation multiple deformed crystalline materials were analyzed using electron backscatter diffraction (EBSD). Deformation experiments were conducted on samples of Solnhofen limestone using a modified Griggs piston cylinder apparatus at UNLV, and also on San Carlos olivine using the D-DIA multi-anvil press at the National Synchrotron Light Source beamline X17B2. Analysis of the mechanical twins in deformed calcite and kink bands in olivine help elucidate deviations in local stress directions away from that of the applied macroscopic stress. Combined calculated compression directions …

Infrared Spectra Analysis Of Thermally Altered Iron Phyllosilicates And The Implications For Mars, William Thomas Bryan

Graduate Theses and Dissertations

This study looks at two iron-rich phyllosilicates, which may be present on Mars. The minerals, greenalite and hisingerite, are rich in iron-II and iron-III, respectively. Small samples (~0.40 grams) of each mineral were crushed and heated in a Lindberg Tube Oven for approximately twenty-four hours at temperatures selected to mimic lava flows and impact events. Following heating, each sample was placed in a Fourier Transform Infrared (FT-IR) spectrometer to collect the near- and mid-infrared spectra. The spectra allowed for these terrestrial analogs to be analyzed with regards to how their structure breaks down with increasing temperature. The samples' colors were …

Microstructures And Quartz Lattice-Preferred Orientations In The Eclogite-Bearing Migmatitic Gneisses Of The D’Entrecasteaux Islands, Papua New Guinea, T. A. Little, B. R. Hacker, S. J. Brownlee, G. Seward

Environmental Science and Geology Faculty Research Publications

Lattice preferred orientations (LPO) of quartz in gneiss domes of the D’Entrecasteaux Islands, Woodlark Rift shed insight into exhumation of the world’s youngest (~5–7Ma) eclogite-bearing terrane at cm/yr rates. We focus on deformation that affected the terrane as it transited between lower crustal depths and the surface, including: (1) grain-scale deformation mechanisms; and (2) style of flow and mode of emplacement of the domes. Electron-backscatter diffraction was used to analyze microstructure and LPOs of 37 quartzofeldspathic gneiss samples that enclose meter-scale mafic blocks preserving original eclogite-facies assemblages. During exhumation of the ultrahigh-pressure (UHP) terrane, gneisses were retrogressed in the amphibolite …

Ore And Gangue Mineral Paragenesis Of The Cortez Hills Carlin-Type Gold Deposit, Nevada: Evidence For Coincident High-Grade Gold Deposition And Collapse Brecciation, Lindsey R. Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Cortez Hills Carlin-type gold deposit (CTGD), located on the Battle Mountain-Eureka trend of Northern NV, is hosted in a conical shaped polylithic breccia whose central axis strikes parallel to the imbricate Voodoo fault system. Gold grades at the center of the Cortez Hills Breccia Zone (CHBZ) are locally in excess of an ounce per ton. Gold mineralization within the refractory ore at Cortez Hills shares many characteristics with other well studied CTGDs. However, new observations during this study have recognized 1) fragmented realgar that are rimmed by gold-bearing iron-sulfide minerals in four samples, 2) a Hg- and Tl-rich late-ore …

Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank

STAR Program Research Presentations

Jupiter’s satellite Europa, whose surface is composed of ice with a possible water ocean beneath, could conceivably serve as an abode for extraterrestrial life. This and other icy celestial bodies may contain organic macromolecular solid material that is produced when surface ices are exposed to ultraviolet radiation and/or electrical energy. Tidal and tectonic stresses or meteorite impacts in icy crusts may produce electrical discharges, which would provide the energy for in-situ synthesis of the organic solids. This electrical energy can be provided by positive hole charge carrier activation. Positive holes exhibit properties such as the ability to flow out of …

Raman Mapping Of Mars Relevant Minerals Using Multiple Excitation Wavelenghts, Victoria Campbell, William Abbey

STAR Program Research Presentations

The purpose of this project is to map Mars relevant minerals using the Raman instrument Horiba LabRam Raman. The Raman spectrometer is a non-invasive sampling technique used to identify mineral composition of various compositions by measuring the “Raman Shift” of each mineral. This was accomplished by using a green (532nm) laser which acted as a monochromatic light source. This source was absorbed by the sample and reemitted. The frequency of the reemitted photons are then shifted up or down in comparison with original frequency, which is referred to as the ‘Raman Effect’. The samples with shorter wavelengths produced a stronger …

Examination Of Spatial Variations In Recrystallization Mechanisms In Quartz, Emma N. Beck

Honors Theses

S-C mylonites form as a result of non-coaxial deformation in ductile shear zones. Planes of weakness develop and delineate two domains, the S and the C Each of these domains accommodates variable amounts of strain. Sample WMSZ-188 exhibits subgrain rotation (SGR) recrystallization in the C domains, and grain boundary migration (GBM) recrystallization in the S domains. This partitioning of recrystallization mechanisms indicates either: (1) strain-rate partitioning during a single deformation event; or (2) a second, lower-temperature deformation event that over-printed the C domains. This study tests these two hypotheses. Optical and EBSD analyses were used to look for evidence of …

Identifying And Tracking Proteins Through The Marine Water Column: Insights Into The Inputs And Preservation Mechanisms Of Protein In Sediments, Eli K. Moore, Brook L. Nunn, David R. Goodlett, H. Rodger Harvey

OES Faculty Publications

Proteins generated during primary production represent an important fraction of marine organic nitrogen and carbon, and have the potential to provide organism-specific information in the environment. The Bering Sea is a highly productive system dominated by seasonal blooms and was used as a model system for algal proteins to be tracked through the water column and incorporated into detrital sedimentary material. Samples of suspended and sinking particles were collected at multiple depths along with surface sediments on the continental shelf and deeper basin of the Bering Sea. Modified standard proteomic preparations were used in conjunction with high pressure liquid chromatography-tandem …

Documenting Magma Evolution Of The Fossa Delle Felci (Salina Island, South Tyrrhenian Sea) By Integrating In Situ Plagioclase Data With Quantitative Modeling, Aaron Mayfield

All Master's Theses

Compositional diversity occurs via processes dominated by recharge, assimilation and fractional crystallization (RAFC), quantification of which can provide insights into eruption catalysts, and therefore assist in hazard mitigation. This study evaluates the relative roles of RAFC processes in Fossa delle Felci (Salina Island, Italy) magmas, which span the basalt to dacite range (52-65 wt% SiO2). Integration of petrographic, whole rock, and in situ plagioclase data with quantitative magma chamber models suggests differentiation dominated by fractional crystallization and magma recharge/mixing in reservoirs located at different crustal levels. At ~12 km depth, magma evolved through crystallization of a pyroxene dominated assemblage; plagioclase …

Documenting Magnatic Processes At Filicudi Island, Aeolian Arc, Italy: Integrating Quantitative Modeling And Plagioclase Textural And In Situ Compositional Data, Michelle Harris

All Master's Theses

Documenting the physiochemical processes that influence magma composition is critical for forecasting eruption styles and managing volcanic hazards. Compositional diversity of magmas develops through recharge, assimilation, and fractional crystallization (RAFC) within subvolcanic magma reservoirs. Integration of MELTS modeling, whole rock, plagioclase textural and in situ elemental and isotopic data from Filicudi Island, Italy allow documentation of the roles and relative chronology that RAFC played in the magmatic evolution and elucidates aspects of the magma plumbing system structure.

Results indicate a polybaric magma plumbing system with deeper (3.5-4 kilobars) and shallower (0.5-1.2 kilobars) storage regions. Within the deeper system, FC acted …

Documenting The Origin Of Compositional Diversity Of Subduction Zone Magmatism, Alicudi, Aeolian Arc (Southern Tyrrhenian Sea, Italy) Using In Situ Plagioclase Data, Rachel Hunt

All Master's Theses

Processes that generate magma compositional diversity are important to document because composition affects degree of explosivity, which impacts hazard mitigation. Magnesium to silicon rich magmas are produced by processes such as magma recharge, assimilation, and fractional crystallization (RAFC) that occur in subvolcanic magma chamber(s). This study evaluates how magma chamber processes contribute to compositional diversity at Alicudi Volcano, Italy. Analytical and petrographic data from ten samples that span the subaerial history include whole rock major and trace elements and strontium/neodymium isotopes, and plagioclase textural types, major and trace elements, and strontium isotopes; numerical modeling was also conducted. Integration of these …

Measurement Of Luminescent Banding In Speleothems: Some Techniques And Limitations, Bryan E. Crowell, William B. White

International Journal of Speleology

Speleothems, especially flowstone and cylindrical stalagmites, exhibit phosphorescence which is often banded on the scale of a few tens of micrometers. The luminescence bands are paleoclimatic records with a very high temporal resolution. A technique has been developed using a laser source and a high resolution Raman spectrometer with microscope and computer-controlled translation stage for both luminescence profiles and luminescence spectroscopy. Luminescence intensity could be measured as a function of traverse distance with a spatial resolution of 2 – 3 μm. Potential sources of error include loss of intensity due to radiation damage by the laser beam, irregularities, cracks, and …

Microstructural Characterization Of Kinked Germanate Olivine Grains, Alex Gregory Drue

UNLV Theses, Dissertations, Professional Papers, and Capstones

Olivine is the most common and the weakest mineral in the upper mantle. Thus the strength of olivine controls the rheology of the earth's upper mantle. The rheology of olivine in the upper mantle has important implications for mantle flow, mountain building, and rates of isostatic adjustment. Recent experimental measurements of the flow strength of deformed olivine polycrystals have assumed a homogeneous state of stress. X-ray synchrotron diffraction experiments have implied that this assumption is not always valid. Elastic Plastic Self Consistent (EPSC) modeling offers an approach to estimating the flow strength of olivine that does not assume a homogeneous …

Depositional Fluxes And Concentrations Of 7Be And 210Pb In Bulk Precipitation And Aerosols At The Interface Of Atlantic And Mediterranean Coasts In Spain, R. L. Lozano, E. G. San Miguel, J. P. Bolívar, M. Baskaran

Environmental Science and Geology Faculty Research Publications

Bulk depositional fluxes of ⁷Be and ²¹⁰Pb in precipitation measured over a period of 16 months (April 2009–July 2010) in Huelva, Spain varied between 5.6 and 186 Bq m⁻² month⁻¹ (annual mean: 834 Bq m⁻² year⁻¹) and 0.8 and 8.1 Bq m⁻² month⁻¹ (annual mean: 59 Bq m⁻² year⁻¹), respectively, with the lowest depositional fluxes occurring during dry summer months. Quantitative evaluation of the precipitation-normalized seasonal depositional fluxes of ⁷Be and ²¹⁰Pb indicates that the enrichment factor in winter is < 1.0 while in 2010 spring, it is significantly higher than 1, possibly indicating input of air from the stratosphere-troposphere exchange (for ⁷Be). The specific activities of …

Magnetic Properties Of Ilmenite‐Hematite Single Crystals From The Ecstall Pluton Near Prince Rupert, British Columbia, Sarah J. Brownlee, Joshua M. Feinberg, Takeshi Kasama, Richard J. Harrison, Gary R. Scott, Paul R. Renne

Environmental Science and Geology Faculty Research Publications

Paleomagnetic studies of the 91 Ma Ecstall pluton and other Cretaceous plutons of British Columbia imply large northward tectonic movements (>2000 km) may have occurred during the tectonic evolution of western North America. However, more recent studies have shown that the eastern edge of the Ecstall pluton experienced considerable mineralogical changes as younger Eocene plutons, such as the ∼58 Ma Quottoon Pluton, were emplaced along its margins. We investigated changes in the rock magnetic properties associated with this reheating event by examining isolated grains of intergrown ilmenite and hematite, the primary paleomagnetic recorder in the Ecstall pluton. Measurements of …

High Pressure Structural Studies On Baco3 Up To 20 Gpa, Justine Carryer, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

Carbonate compounds are thought to make up a minor portion of the Earth's upper mantel. Shock heating of the surfaces of carbonate rocks, as in the instance of a meteor impact, has the potential to affect CO2 concentrations in the Earth's atmosphere. The bulkmodulus of carbonate materials is directly proportional to the rate of devolatilization under these conditions [1]. The interest in Barium Carbonate (BaCO3) specifically is motivated by its structural proximity to aragonite carbonates. Crystalline phase transitions occur in aragonite under extreme conditions that are difficult to maintain in a laboratory; BaC03 is isostructural with aragonite and therefore is …

Correlation Between Grain Dislocation Density And Orientation For Naturally Deformed Mantle Xenolith From Jagersfontein Mine, Quinton Guerrero, Quinlan Smith

Undergraduate Research Opportunities Program (UROP)

Determining the reaction of poly-crystalline structures to induced stress is an extremely difficult problem in contemporary engineering and geology. The main challenge lies in the inhomogeneity of the grains inside of the poly-crystalline structures. To predict the response of a certain polycrystalline structure to a specific stress, you must resort to one of two views on grain interaction, an orientation or propagation based model. For every material there may be certain correlations between the prediction model used and the actual deformation that occurred. Our work centers around describing the correlation of these prediction models with a sample of naturally deformed …

Investigation Of Raman Active Modes Of Mgxzn1-Xcr2o4, Nichollas Macholl, Tyler Mosher

Undergraduate Research Opportunities Program (UROP)

Using Raman spectroscopy, vibrational modes of the spinel structure MgxZn1-xCr2O4 were experimentally examined. The spinel compounds were synthesized by producing solid solutions via combustion method, of MgxZn1-xCr2O4 in the range x=0 to x=1 in 0.1 intervals. The purpose of which was to experimentally verify gradual shifts of Raman peaks as the samples transitioned between the two different compounds and gain information about the dependencies of the lattice vibrations on the tetrahedral and octahedral cations. X-ray diffraction was also used to verify spinel structure, and track the changes in lattice parameter of the samples.

Rock Porosity Analysis Using High Resolution X-Ray Tomography, Leo Groner, Dula Parkinson, Katya Bazilevskaya

STAR Program Research Presentations

Understanding rock porosity, the fraction of rock volume that is in pores, is a key to modeling weathering and flow of water, petroleum and CO2 through geological structures. Weathering of rocks affects the CO2 cycle, nutrient cycle and soil formation. Rock porosity affects water flow rates and, in turn, affects weathering. Avizo software was used to explore, visualize and measure the reconstructed high-resolution X-ray micro-tomography data collected from scanned rocks. Many Avizo approaches were tried before arriving at an acceptable process to determine their porosity characteristics. Porosity dynamics are affected by weathering and lithification. At micron resolution, the image is …

Raman Spectroscopic Study Of Solid Solution Spinel Oxides, Brian D. Hosterman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Solid solution spinel oxides of composition MgxNi1−xCr2O4, NiFexCr2−xO4, and FexCr3−xO4 were synthesized and characterized using x-ray diffraction and Raman spectroscopy. Frequencies of the Raman-active modes are tracked as the metal cations within the spinel lattice are exchanged. This gives information about the dependence of the lattice vibrations on the tetrahedral and octahedral cations. The highest-frequency Raman-active mode, A1g, is unaffected by substitution of the divalent tetrahedral cation, whereas the lower frequency vibrations are more strongly affected by substitution of the tetrahedral cation. The change in wavenumber of many phonons is nonlinear upon cation exchange. All detected modes of MgxNi1−xCr2O4 and …

Elastic Plastic Self Consistent (Epsc) Modeling Of Plastic Deformation In Fayalite Olivine, Christopher J. Cline Ii, Pamela Burnley

Festival of Communities: UG Symposium (Posters)

We are using an Elastic Plastic Self Consistent Model (a type of numerical simulation) to study deformation of olivine. Olivine is one of the major constituents of the Earth’s upper mantle and its deformation properties have an important influence on how the Earth’s crust deforms. For example, the flow strength of olivine limits the size of the largest earthquakes and the heights of the tallest mountains on Earth. By comparing the results of our simulations with data from olivine deformation experiments we are able to better interpret the experimental data.

Revisiting Three Minerals From Cioclovina Cave (Romania), Bogdan P. Onac, Herta S. Effenberger, Nathan C. Collins, Joe B. Kearns, Radu C. Breban

International Journal of Speleology

Cioclovina Cave in Romania’s Southern Carpathians is a world-renowned cave site for its paleontological, anthropological, and mineralogical (type locality of ardealite) findings. To date, over 25 mineral species have been documented, some unusual for a cave environment. This paper presents details on the occurrence of collinsite [Ca₂(Mg,Fe²⁺)(PO₄)₂·2H₂O], atacamite [Cu₂²⁺Cl(OH)₃], and kröhnkite [Na₂Cu²⁺(SO₄)₂·2H₂O] based on single-crystal X-ray diffraction, electron microprobe, stable isotope analyses, and scanning electron microscope imaging. This is the first reported occurrence of kröhnkite …

Secondary Halite Deposits In The Iranian Salt Karst: General Description And Origin, Michal Filippi, Jiří Bruthans, Lukáš Palatinus, Mohammad Zare, Naser Asadi

International Journal of Speleology

This paper summaries 12 years of documentation of secondary halite deposits in the Iranian salt karst.

A variety of secondary halite deposits was distinguished and classified into several groups, on the basis of the site and mechanism of their origin. Deposits formed: i) via crystallization in/on streams and pools, ii) from dripping, splashing and aerosol water, iii) from evaporation of seepage and capillary water, and iv) other types of deposits. The following examples of halite forms were distinguished in each of the above mentioned group: i) euhedral crystals, floating rafts (raft cones), thin brine surface crusts and films; ii) straw …