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Enstatite Achondrites As Indicators Of Processes And Environments In The Early Solar System, Diego David Uribe 2017 The University of Western Ontario

Enstatite Achondrites As Indicators Of Processes And Environments In The Early Solar System, Diego David Uribe

Electronic Thesis and Dissertation Repository

This thesis investigates the processes and environments of formation of the anomalous enstatite achondrites NWA 4301, Zakłodzie, and NWA 8173 to determine how they relate to other enstatite meteorites (chondrites, impact melt rocks, aubrites, and so-called “primitive enstatite achondrites”). Observations of Zakłodzie and NWA 4301 showed both meteorites may share a common parent body, but experienced different metamorphic conditions. Different zonation patterns in plagioclase, silica polymorphs and associations, and sulfide assemblages indicate Zakłodzie experienced higher metamorphic temperatures and cooled faster than NWA 4301, therefore NWA 4301 was buried deeper in the parent body relative to Zakłodzie. In NWA 8173, mineral ...


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 2017 University of New Mexico

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 ...


Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali 2017 University of Kentucky

Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali

Chemistry Faculty Publications

How primordial metabolic networks such as the reverse tricarboxylic acid (rTCA) cycle and clay mineral catalysts coevolved remains a mystery in the puzzle to understand the origin of life. While prebiotic reactions from the rTCA cycle were accomplished via photochemistry on semiconductor minerals, the synthesis of clays was demonstrated at low temperature and ambient pressure catalyzed by oxalate. Herein, the crystallization of clay minerals is catalyzed by succinate, an example of a photoproduced intermediate from central metabolism. The experiments connect the synthesis of sauconite, a model for clay minerals, to prebiotic photochemistry. We report the temperature, pH, and concentration dependence ...


Stable Isotope Chemistry In Titan Haze Aerosol, Allison Wold 2017 University of Northern Iowa

Stable Isotope Chemistry In Titan Haze Aerosol, Allison Wold

Research in the Capitol

Titan, a moon of Saturn, has a thick atmosphere made up of nitrogen and a few percent methane, with a surface pressure of 1.5x that of Earth. Titan’s atmosphere is believed to be that similar to that of early Earth before the rise of O2. One significant source of information on the history and evolution of the atmosphere is the measurement of stable isotopes of elements in the molecules of major gases such as nitrogen, methane, and higher order hydrocarbons. The fractionation associated with the formation of Titan aerosol analogs are explored in the laboratory as a function ...


Petrography, Stable Isotope Compositions, Microraman Spectroscopy, And Presolar Components Of Roberts Massif 04133: A Reduced Cv3 Carbonaceous Chrondrite, Jemma Davidson, Devin L. Schrader, Conel M. Alexander, Dante S. Lauretta, Henner Busemann, Ian A. Franchi, Richard C. Greenwood, Harold Connolly Jr., Kenneth J. Domanik, Alexander Verchovsky 2016 Selected Works

Petrography, Stable Isotope Compositions, Microraman Spectroscopy, And Presolar Components Of Roberts Massif 04133: A Reduced Cv3 Carbonaceous Chrondrite, Jemma Davidson, Devin L. Schrader, Conel M. Alexander, Dante S. Lauretta, Henner Busemann, Ian A. Franchi, Richard C. Greenwood, Harold Connolly Jr., Kenneth J. Domanik, Alexander Verchovsky

Harold Connolly

Here, we report the mineralogy, petrography, C-N-O-stable isotope compositions, degree of disorder of organic matter, and abundances of presolar components of the chondrite Roberts Massif (RBT) 04133 using a coordinated, multitechnique approach. The results of this study are inconsistent with its initial classification as a Renazzo-like carbonaceous chondrite, and strongly support RBT 04133 being a brecciated, reduced petrologic type >3.3 Vigarano-like carbonaceous (CV) chondrite. RBT 04133 shows no evidence for aqueous alteration. However, it is mildly thermally altered (up to approximately 440 °C); which is apparent in its whole-rock C and N isotopic compositions, the degree of disorder of ...


Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman 2016 University of Kentucky

Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

The reductive tricarboxylic acid (rTCA) cycle is an important central biosynthetic pathway that fixes CO2 into carboxylic acids. Among the five reductive steps in the rTCA cycle, the two-electron reduction of fumarate to succinate proceeds nonenzymatically on the surface of photoexcited sphalerite (ZnS) colloids suspended in water. This model reaction is chosen to systematically study the surface photoprocess occurring on ZnS in the presence of [Na2S] (1–10 mM) hole scavenger at 15 °C. Experiments at variable pH (5–10) indicate that monodissociated fumaric acid is the primary electron acceptor forming the monoprotic form of succinic acid ...


40ar/39ar Ages Of Lunar Impact Glasses: Relationships Among Ar Diffusivity, Chemical Composition, Shape, And Size, John W. Delano PhD, Nicolle Zellner 2015 University at Albany, State University of New York

40ar/39ar Ages Of Lunar Impact Glasses: Relationships Among Ar Diffusivity, Chemical Composition, Shape, And Size, John W. Delano Phd, Nicolle Zellner

Atmospheric and Environmental Science Faculty Scholarship

Lunar impact glasses, which are quenched melts produced during cratering events on the Moon, have the potential to providenot only compositional information about both the local and regional geology of the Moon but also information about the impact flux over time. We present in this paper the results of 73 new 40Ar/39Ar analyses of well-characterized, inclusion-free lunar impact glasses and demonstrate that size, shape, chemical composition, fraction of radiogenic 40Ar retained, and cosmic ray exposure (CRE) ages are important for 40Ar/39Ar investigations of these samples. Specifically, analyses of lunar impact glasses from the Apollo 14, 16, and 17 ...


Insights Into Planetesimal Evolution: Petrological Investigations Of Regolithic Howardites And Carbonaceous Chondrite Impact Melts, Nicole Gabriel Lunning 2015 University of Tennessee - Knoxville

Insights Into Planetesimal Evolution: Petrological Investigations Of Regolithic Howardites And Carbonaceous Chondrite Impact Melts, Nicole Gabriel Lunning

Doctoral Dissertations

Asteroidal meteorites are the only available geologic samples from the early part of our solar system’s history. These meteorites contain evidence regarding how the earliest protoplanetary bodies formed and evolved. I use petrological and geochemical techniques to investigate the evolution of these early planetesimals, focusing on two meteorite types: Howardites, which are brecciated samples of a differentiated parent body (thought to be the asteroid 4 Vesta), and CV chondrites, which are primitive chondrites that have not undergone differentiation on their parent body.

Quantitative petrological analysis and characterization of paired regolithic (solar wind-rich) howardites indicate that this large sample of ...


Hunting Starstuff: Searching For Calcium-Aluminum-Rich Inclusions In Cometary Dust, Christian Engelbrecht 2014 Space Sciences Laboratory

Hunting Starstuff: Searching For Calcium-Aluminum-Rich Inclusions In Cometary Dust, Christian Engelbrecht

STAR (STEM Teacher and Researcher) Presentations

NASA’s Stardust mission (1999 - 2006) returned physical samples of the particles ejected by the comet 81P/Wild 2, collected in ultralight and extremely low density aerogel. These samples have been extensively analyzed using X-Ray Fluorescence (XRF), among other techniques, to determine the elemental, chemical and mineralogical composition of Wild 2. Because comets are thought to be formed in the icy outer regions of the solar system, billions of years ago, the Stardust data gives us details of the composition of the ancient solar system and its subsequent evolution. One of the surprises to come out of the data is ...


Exploring Martian Magmas: From The Mantle To The Regolith, Arya Sigrid Waltraud Udry 2014 University of Tennessee - Knoxville

Exploring Martian Magmas: From The Mantle To The Regolith, Arya Sigrid Waltraud Udry

Doctoral Dissertations

The planet Mars is geologically more similar to Earth than to other planets of the solar system. For the past 50 years, new rovers, orbital spacecraft, and new martian meteorites have helped us to understand the geological processes that occurred on Mars. In this dissertation, I investigate a wide range of martian igneous compositions, such as shergottite and nakhlite meteorites, Gusev and Gale surface basalts, and the Northwest Africa (NWA) 7034 breccia. I attempt to better understand magmatic processes that occurred in the martian mantle and crust as well as surficial processes using various petrologic and geochemical tools.

As shown ...


The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman 2014 Washington University in St. Louis - Physics Department

The Stardust Interstellar Dust Collector Crater Origins And Hypervelocity Cratering At Oblique Angles In Aluminum Foil, Harison Wiesman

Undergraduate Theses—Unrestricted

From 1999 to 2006 the NASA Stardust mission collected cometary particles from the Wild 2 comet and interstellar dust from the interstellar medium in two collectors made from aerogel tiles and aluminum foil. By studying their isotopic compositions, these particles can provide us with information about nucleosynthetic processes in stars. Both collector trays are being studied for traces of these particles, though a number of challenges have arisen in doing so. Identifying impact craters in the aluminum foil on the interstellar collector tray has been incredibly difficult. In addition to being only a few micrometers or less in diameter, many ...


Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman 2014 Washington University in St. Louis - Physics Department

Survey Of ‘Low-Z’ Particles From The Interplanetary Dust Collection In Search Of Idps, Harison Wiesman

Undergraduate Theses—Unrestricted

Micrometeorites are one of the most common types of extraterrestrial material that fall to the Earth, beside meteorites and interplanetary dust particles (IDPs). All of these materials are known to contain presolar grains that, when studied in the laboratory, provide information about the origin of the solar system and help to constrain models of nucleosynthesis in stars. Recent studies of micrometeorites revealed the presence of a group of particles with very high C contents. These ultra-carbonaceous Antarctic micrometeorites (UCAMMs) are fine-grained, fluffy particles dominated by highly disordered carbonaceous matter. The presence of H and N isotopic anomalies, abundant presolar grains ...


Petrography, Stable Isotope Compositions, Microraman Spectroscopy, And Presolar Components Of Roberts Massif 04133: A Reduced Cv3 Carbonaceous Chrondrite, Jemma Davidson, Devin L. Schrader, Conel M. Alexander, Dante S. Lauretta, Henner Busemann, Ian A. Franchi, Richard C. Greenwood, Harold Connolly Jr., Kenneth J. Domanik, Alexander Verchovsky 2014 Rowan University

Petrography, Stable Isotope Compositions, Microraman Spectroscopy, And Presolar Components Of Roberts Massif 04133: A Reduced Cv3 Carbonaceous Chrondrite, Jemma Davidson, Devin L. Schrader, Conel M. Alexander, Dante S. Lauretta, Henner Busemann, Ian A. Franchi, Richard C. Greenwood, Harold Connolly Jr., Kenneth J. Domanik, Alexander Verchovsky

School of Earth & Environment Faculty Scholarship

Here, we report the mineralogy, petrography, C-N-O-stable isotope compositions, degree of disorder of organic matter, and abundances of presolar components of the chondrite Roberts Massif (RBT) 04133 using a coordinated, multitechnique approach. The results of this study are inconsistent with its initial classification as a Renazzo-like carbonaceous chondrite, and strongly support RBT 04133 being a brecciated, reduced petrologic type >3.3 Vigarano-like carbonaceous (CV) chondrite. RBT 04133 shows no evidence for aqueous alteration. However, it is mildly thermally altered (up to approximately 440 °C); which is apparent in its whole-rock C and N isotopic compositions, the degree of disorder of ...


Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindschadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, Desert Research Institute, Reno, NV, C. O. Justice, Ayse Irmak, V. Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. McCorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu 2014 South Dakota State University

Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindschadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, Desert Research Institute, Reno, Nv, C. O. Justice, Ayse Irmak, V. Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. Mccorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu

Papers in Natural Resources

Landsat 8, a NASA and USGS collaboration, acquires global moderate-resolution measurements of the Earth's terrestrial and polar regions in the visible, near-infrared, short wave, and thermal infrared. Landsat 8 extends the remarkable 40 year Landsat record and has enhanced capabilities including new spectral bands in the blue and cirrus cloud-detection portion of the spectrum, two thermal bands, improved sensor signal-to-noise performance and associated improvements in radiometric resolution, and an improved duty cycle that allows collection of a significantly greater number of images per day. This paper introduces the current (2012–2017) Landsat Science Team's efforts to establish an ...


Ballistics Analysis Of Volcanic Ejecta: Miter Crater, Ice Springs Volcanic Field, Black Rock Desert, Utah, William Cary 2013 The College of Wooster

Ballistics Analysis Of Volcanic Ejecta: Miter Crater, Ice Springs Volcanic Field, Black Rock Desert, Utah, William Cary

Senior Independent Study Theses

Ice Springs Volcanic Field, located in the Black Rock Desert west of Fillmore, Utah, is composed of three large craters, Crescent, Miter, and Terrace, and several smaller craters. Concern over the hazards of the volcanic field, ±660 years old, reactivating prompted the creation of a hazards model. This study focuses on Miter Crater in order to conduct a ballistic analysis of the blocks and bombs observed along the crater rim. Data analysis of Miter Crater ejecta was then used to create a hazards model for ballistic volcanic ejecta. Thirty-four blocks and bombs were recorded along the rim of Miter Crater ...


Crystal Structure And Al/Si Cation Ordering In "Fassaite": A Combined Single Crystal, 27al And 29si Nmr Study, Monika M. Haring 2012 The University of Western Ontario

Crystal Structure And Al/Si Cation Ordering In "Fassaite": A Combined Single Crystal, 27al And 29si Nmr Study, Monika M. Haring

Electronic Thesis and Dissertation Repository

Al-,Ti-rich diopside, referred to herein as fassaite, occurs in both terrestrial and extraterrestrial environments. The composition of fassaite, Ca(Mg,Al)(Si,Al)2O6, makes it ideal for Al/Si cation ordering studies. In this study, crystal XRD, 27Al and 29Si MAS NMR as well as 27Al 3QMAS NMR is used to study cation ordering in extraterrestrial fassaite from Allende CAIs and a terrestrial analogue from Fassa Valley Italy. From 27Al and 29Si spectroscopy, fassaite from Allende CAIs is found to have more local Al/Si cation ordering than terrestrial Fassaite. Both terrestrial ...


Identification Of An Unknown Meteorite Found In North Africa, Carroll C. Rigler 2012 University of Tennessee - Knoxville

Identification Of An Unknown Meteorite Found In North Africa, Carroll C. Rigler

University of Tennessee Honors Thesis Projects

No abstract provided.


Geochemical And Field Relationships Of Pillow And Dike Units In A Subglacial Pillow Unit Undirhliđar Quarry, Southwest Iceland, Lindsey J. Bowman 2012 The College of Wooster

Geochemical And Field Relationships Of Pillow And Dike Units In A Subglacial Pillow Unit Undirhliđar Quarry, Southwest Iceland, Lindsey J. Bowman

Senior Independent Study Theses

Undirhlíðar quarry is located on the Sveifluhals ridge, a Pleistocene subglacial pillow ridge within the NE-SW trending Krísuvík fissure swarm on the Reykjanes peninsula in Southwest Iceland. The walls of Undirhlíðar quarry provide excellent exposures of the internal architecture of the pillow ridge, yielding insights into the sequence of eruptive and intrusive events that construct subglacial ridges. In particular, the south and east walls expose at least 5 different pillow units and 3 dikes. Also seen in the east wall is a black, glassy breccia unit that appears on both the north and south sections of the east wall. Preliminary ...


Laboratory Astrophysics: Using Ebit Measurements To Interpret High Resolution Spectra From Celestial Sources, Carey Scott, Joshua Thompson, N. Hell, Greg V. Brown 2011 California State University - Chico

Laboratory Astrophysics: Using Ebit Measurements To Interpret High Resolution Spectra From Celestial Sources, Carey Scott, Joshua Thompson, N. Hell, Greg V. Brown

STAR (STEM Teacher and Researcher) Presentations

Astrophysicists use radiation to investigate the physics controlling a variety of celestial sources, including stellar atmospheres, black holes, and binary systems. By measuring the spectrum of the emitted radiation, astrophysicists can determine a source’s temperature and composition. Accurate atomic data are needed for reliably interpreting these spectra. Here we present an overview of how LLNL’s EBIT facility is used to put the atomic data on sound footing for use by the high energy astrophysics community.


Serpentinite Weathering And Implications For Mars, Valerie Tu, Julie Baumeister, Rodney Metcalf, A. Olsen, Elisabeth Hausrath 2011 University of Nevada, Las Vegas

Serpentinite Weathering And Implications For Mars, Valerie Tu, Julie Baumeister, Rodney Metcalf, A. Olsen, Elisabeth Hausrath

Festival of Communities: UG Symposium (Posters)

In the search for life on Mars near-surface soil environments may be important habitats for life accessible to future missions. Serpentinite rocks have been documented on Mars, as well as other clay minerals including smectite and kaolinites. Previous studies of soils formed on serpentinites on Earth have documented the formation of extensive clays. Serpentinites are additionally of interest as habitats for life such as methanogens. Here we examine weathering of serpentinites from bedrock to soil surface, as a potential route for the formation of clay minerals on Mars from abundant ultramafic minerals. We additionally test for the presence of Fe-oxidizing ...


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