Computational Methods for High Energy Physics
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A New Primitive Achondrite from Northwest Africa
A New Primitive Achondrite from Northwest Africa Kseniya K. Androsova* University of Calgary, Calgary, AB, Canada [email protected] and Alan R. Hildebrand University of Calgary, Calgary, AB, Canada Summary The winonaite and acapulcoite/lodranite meteorites constitute small groups of primitive achondrites that have experienced thermal metamorphism sometimes accompanied by varying degrees of partial melting. Petrographic and elemental abundance studies [optical microscope observations and electron microprobe analysis] have been conducted on several meteorites recovered in Northwest Africa (NWA). One meteorite has fine-grained, granulitic texture, abundant, evenly distributed metal and troilite grains, and highly reduced mineral compositions [Olivine (Fa6.0±0.4), low-Ca pyroxene (Fs7.5±0.4, Wo1.3±0.2), high-Ca pyroxene (Fs3.2±0.2, Wo45.8±0.7)]. Based on these criteria it appears that the data are consistent with the sample being a winonaite. The overall textural resemblance of this meteorite to NWA 1463 and /or NWA 725 (somewhat anomalous) winonaites (both having multiple relict chondrules) may suggest that this meteorite is paired with one or both. Although, until its oxygen isotope composition is obtained the classification of this meteorite as a winonaite (vs. as an acapulcoite) remains uncertain, its primitive achondritic nature is quite evident. Introduction The winonaite meteorites represent a class of rare primitive achondrites (together with the acapulcoite/lodranite association) that have sometimes undergone partial melting but generally have chondritic mineralogy and composition. Winonaites can be characterized by fine- to medium-grained, mostly granulitic textures, highly reduced mineral compositions, and unique oxygen isotope signatures (Benedix et al., 1998). Although most of the winonaites lack chondrules, several have been reported to have regions containing relict chondrules. -
Siderophile Elements and Molybdenum, Tungsten, And
ABSTRACT Title of Dissertation: SIDEROPHILE ELEMENTS AND MOLYBDENUM, TUNGSTEN, AND OSMIUM ISOTOPES AS TRACERS OF PLANETARY GENETICS AND DIFFERENTIATION: IMPLICATIONS FOR THE IAB IRON METEORITE COMPLEX Emily Anne Worsham, Doctor of Philosophy, 2016 Dissertation directed by: Professor Richard Walker, Department of Geology Isotopic and trace element abundance data for iron meteorites and chondrites are presented in order to investigate the nature of genetic relations between and among meteorite groups. Nebular and planetary diversity and processes, such as differentiation, can be better understood through study of IAB complex iron meteorites. This is a large group of chemically and texturally similar meteorites that likely represent metals with a thermal history unlike most other iron meteorite groups, which sample the cores of differentiated planetesimals. The IAB complex contains a number of chemical subgroups. Trace element determination and modeling, Re/Os isotopic systematics, nucleosynthetic Mo isotopic data, and 182Hf-182W geochronology are used to determine the crystallization history, genetics, and relative metal-silicate segregation ages of the IAB iron meteorite complex. Highly siderophile element abundances in IAB complex meteorites demonstrate that diverse crystallization mechanisms are represented in the IAB complex. Relative abundances of volatile siderophile elements also suggest late condensation of some IAB precursor materials. Improvements in the procedures for the separation, purification, and high- precision analysis of Mo have led to a ~2 fold increase in the precision of 97Mo/96Mo isotope ratio measurements, compared to previously published methods. Cosmic ray exposure-corrected Mo isotopic compositions of IAB complex irons indicate that at least three parent bodies are represented in the complex. The Hf-W metal-silicate segregation model ages of IAB complex subgroups suggests that at least four metal segregation events occurred among the various IAB parent bodies. -
UNIVERSITY of CALIFORNIA, SAN DIEGO Primitive and Differentiated
UNIVERSITY OF CALIFORNIA, SAN DIEGO Primitive and differentiated achondrite meteorites and partial melting in the early Solar System A Thesis submitted in partial satisfaction of the requirements for the degree Master of Science in Earth Sciences By Christopher Andrew Corder Committee in charge: Professor James M. D. Day, Chair Professor Geoffrey W. Cook Professor David R. Stegman 2015 © Christopher Andrew Corder, 2015 All rights reserved. The Thesis of Christopher Corder is approved and it is acceptable in quality and form for publication on microfilm and electronically: Chair University of California, San Diego 2015 iii Dedication This manuscript would be far from complete without thanking those who helped set the stage for the many hours of work it documents, and those thank-yous would be far from complete without recognizing my parents and their unwavering support throughout years of study. I know I was the one in the lab, but I never would have made it there, or to my defense, or through any of the long days and nights if it weren’t for you both. Thank you, so much. I’d love to thank my entire family, especially Stephen. You’re a brother Stephen, and you encourage me more than you know. Whenever it seemed like research was going nowhere, you were there to remind me why science is always a worthwhile endeavor. Even more importantly you remind me, by example, that there are exceptional people in this world. Many thanks are due to the lab group I worked with and other smart folks at SIO. First of all, thank you James for trusting this intriguing suite of meteorites to my care. -
1 Unique Achondrite Northwest Africa 11042: Exploring the Melting And
Unique achondrite Northwest Africa 11042: Exploring the melting and breakup of the L Chondrite parent body Zoltan Vaci1,2, Carl B. Agee1,2, Munir Humayun3, Karen Ziegler1,2, Yemane Asmerom2, Victor Polyak2, Henner Busemann4, Daniela Krietsch4, Matthew Heizler5, Matthew E. Sanborn6, and Qing-Zhu Yin6 1Institute of Meteoritics, University of New Mexico, Albuquerque, NM. 2Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM. 3National High Magnetic Field Laboratory and Dept. of Earth, Ocean & Atmospheric Science, Florida State University, Tallahassee, FL 32310, USA. 4Institute of Geochemistry and Petrology, ETH Zürich, Zurich, Switzerland. 5New Mexico Bureau of Geology, New Mexico Institute of Mining and Technology, Socorro, NM. 6Department of Earth and Planetary Sciences, University of California-Davis, Davis, CA. Abstract Northwest Africa (NWA) 11042 is a heavily shocked achondrite with medium-grained cumulate textures. Its olivine and pyroxene compositions, oxygen isotopic composition, and chromium isotopic composition are consistent with L chondrites. Sm-Nd dating of its primary phases shows a crystallization age of 4100±160 Ma. Ar-Ar dating of its shocked mineral maskelynite reveals an age of 484.0±1.5 Ma. This age coincides roughly with the breakup event of the L chondrite parent body evident in the shock ages of many L chondrites and the terrestrial record of fossil L chondritic chromite. NWA 11042 shows large depletions in siderophile elements (<0.01×CI) suggestive of a complex igneous history involving extraction of a Fe-Ni-S liquid on the L chondrite parent body. Due to its relatively young crystallization age, the heat source for such an igneous process is most likely impact. -
(2000) Forging Asteroid-Meteorite Relationships Through Reflectance
Forging Asteroid-Meteorite Relationships through Reflectance Spectroscopy by Thomas H. Burbine Jr. B.S. Physics Rensselaer Polytechnic Institute, 1988 M.S. Geology and Planetary Science University of Pittsburgh, 1991 SUBMITTED TO THE DEPARTMENT OF EARTH, ATMOSPHERIC, AND PLANETARY SCIENCES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN PLANETARY SCIENCES AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY FEBRUARY 2000 © 2000 Massachusetts Institute of Technology. All rights reserved. Signature of Author: Department of Earth, Atmospheric, and Planetary Sciences December 30, 1999 Certified by: Richard P. Binzel Professor of Earth, Atmospheric, and Planetary Sciences Thesis Supervisor Accepted by: Ronald G. Prinn MASSACHUSES INSTMUTE Professor of Earth, Atmospheric, and Planetary Sciences Department Head JA N 0 1 2000 ARCHIVES LIBRARIES I 3 Forging Asteroid-Meteorite Relationships through Reflectance Spectroscopy by Thomas H. Burbine Jr. Submitted to the Department of Earth, Atmospheric, and Planetary Sciences on December 30, 1999 in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Planetary Sciences ABSTRACT Near-infrared spectra (-0.90 to ~1.65 microns) were obtained for 196 main-belt and near-Earth asteroids to determine plausible meteorite parent bodies. These spectra, when coupled with previously obtained visible data, allow for a better determination of asteroid mineralogies. Over half of the observed objects have estimated diameters less than 20 k-m. Many important results were obtained concerning the compositional structure of the asteroid belt. A number of small objects near asteroid 4 Vesta were found to have near-infrared spectra similar to the eucrite and howardite meteorites, which are believed to be derived from Vesta. -
Chondrules Reveal Large-Scale Outward Transport of Inner Solar System Materials in the Protoplanetary Disk
Chondrules reveal large-scale outward transport of inner Solar System materials in the protoplanetary disk Curtis D. Williamsa,1, Matthew E. Sanborna, Céline Defouilloyb,2, Qing-Zhu Yina,1, Noriko T. Kitab, Denton S. Ebelc, Akane Yamakawaa,3, and Katsuyuki Yamashitad aDepartment of Earth and Planetary Sciences, University of California, Davis, CA 95616; bWiscSIMS, Department of Geoscience, University of Wisconsin–Madison, Madison, WI 53706; cDepartment of Earth and Planetary Sciences, American Museum of Natural History, New York, NY 10024; and dGraduate School of Natural Science and Technology, Okayama University, Kita-ku, 700-8530 Okayama, Japan Edited by H. J. Melosh, Purdue University, West Lafayette, IN, and approved August 9, 2020 (received for review March 19, 2020) Dynamic models of the protoplanetary disk indicate there should actually be composed of solids with diverse formation histories be large-scale material transport in and out of the inner Solar Sys- and, thus, distinct isotope signatures, which can only be revealed tem, but direct evidence for such transport is scarce. Here we show by studying individual components in primitive chondritic me- that the e50Ti-e54Cr-Δ17O systematics of large individual chon- teorites (e.g., chondrules). Chondrules are millimeter-sized drules, which typically formed 2 to 3 My after the formation of spherules that evolved as free-floating objects processed by the first solids in the Solar System, indicate certain meteorites (CV transient heating in the protoplanetary disk (1) and represent a and CK chondrites) that formed in the outer Solar System accreted major solid component (by volume) of the disk that is accreted an assortment of both inner and outer Solar System materials, as into most chondrites. -
Oxygen Isotope Variation in Primitive Achondrites: the Influence of Primordial, Asteroidal and Terrestrial Processes
Available online at www.sciencedirect.com Geochimica et Cosmochimica Acta 94 (2012) 146–163 www.elsevier.com/locate/gca Oxygen isotope variation in primitive achondrites: The influence of primordial, asteroidal and terrestrial processes R.C. Greenwood a,⇑, I.A. Franchi a, J.M. Gibson a, G.K. Benedix b a Planetary and Space Sciences, The Open University, Milton Keynes MK7 6AA, UK b Impacts and Astromaterials Research Centre, Department of Mineralogy, Natural History Museum, London SW7 5BD, UK Received 23 September 2011; accepted in revised form 23 June 2012; available online 13 July 2012 Abstract A detailed oxygen isotope study of the acapulcoites, lodranites, winonaites, brachinites and various related achondrites has been undertaken to investigate the nature of their precursor materials. High levels of terrestrial alteration displayed by many of these samples have been mitigated by leaching in ethanolamine thioglycollate (EATG) solution. Due to their high metal and sulphide content, acapulcoite, lodranite and winonaite samples show much greater isotopic shifts during weathering than brachinites. As observed in previous studies, Antarctic weathered finds are displaced to lighter oxygen isotope compositions and non-Antarctic finds to heavier values. Leached primitive achondrite residues continue to show high levels of oxygen isotope heterogeneity. This variation is reflected in the 2r error on group mean D17O values, which decrease in the following order: acapulcoite–lodranite clan > brachinites > winonaites. On an oxygen three-isotope diagram, the acapulcoite––lodranite clan define a limited trend with a slope of 0.61 ± 0.08 and an intercept of À1.43 ± 0.27 (R2 = 0.78). A broad positive correlation between D17O and oliv- ine fayalite contents displayed by both acapulcoite and lodranite samples may be the result of early aqueous alteration and subsequent dehydration. -
Systematics and Evaluation of Meteorite Classification 19
Weisberg et al.: Systematics and Evaluation of Meteorite Classification 19 Systematics and Evaluation of Meteorite Classification Michael K. Weisberg Kingsborough Community College of the City University of New York and American Museum of Natural History Timothy J. McCoy Smithsonian Institution Alexander N. Krot University of Hawai‘i at Manoa Classification of meteorites is largely based on their mineralogical and petrographic charac- teristics and their whole-rock chemical and O-isotopic compositions. According to the currently used classification scheme, meteorites are divided into chondrites, primitive achondrites, and achondrites. There are 15 chondrite groups, including 8 carbonaceous (CI, CM, CO, CV, CK, CR, CH, CB), 3 ordinary (H, L, LL), 2 enstatite (EH, EL), and R and K chondrites. Several chondrites cannot be assigned to the existing groups and may represent the first members of new groups. Some groups are subdivided into subgroups, which may have resulted from aster- oidal processing of a single group of meteorites. Each chondrite group is considered to have sampled a separate parent body. Some chondrite groups and ungrouped chondrites show chemi- cal and mineralogical similarities and are grouped together into clans. The significance of this higher order of classification remains poorly understood. The primitive achondrites include ureil- ites, acapulcoites, lodranites, winonaites, and silicate inclusions in IAB and IIICD irons and probably represent recrystallization or residues from a low-degree partial melting of chondritic materials. The genetic relationship between primitive achondrites and the existing groups of chondritic meteorites remains controversial. Achondrites resulted from a high degree of melt- ing of chondrites and include asteroidal (angrites, aubrites, howardites-diogenites-eucrites, mesosiderites, 3 groups of pallasites, 15 groups of irons plus many ungrouped irons) and plane- tary (martian, lunar) meteorites. -
Compiled Thesis
SPACE ROCKS: a series of papers on METEORITES AND ASTEROIDS by Nina Louise Hooper A thesis submitted to the Department of Astronomy in partial fulfillment of the requirement for the Bachelor’s Degree with Honors Harvard College 8 April 2016 Of all investments into the future, the conquest of space demands the greatest efforts and the longest-term commitment, but it also offers the greatest reward: none less than a universe. — Daniel Christlein !ii Acknowledgements I finished this senior thesis aided by the profound effort and commitment of my thesis advisor, Martin Elvis. I am extremely grateful for him countless hours of discussions and detailed feedback on all stages of this research. I am also grateful for the remarkable people at Harvard-Smithsonian Center for Astrophysics of whom I asked many questions and who took the time to help me. Special thanks go to Warren Brown for his guidance with spectral reduction processes in IRAF, Francesca DeMeo for her assistance in the spectral classification of our Near Earth Asteroids and Samurdha Jayasinghe and for helping me write my data analysis script in python. I thank Dan Holmqvist for being an incredibly helpful and supportive presence throughout this project. I thank David Charbonneau, Alicia Soderberg and the members of my senior thesis class of astrophysics concentrators for their support, guidance and feedback throughout the past year. This research was funded in part by the Harvard Undergraduate Science Research Program. !iii Abstract The subject of this work is the compositions of asteroids and meteorites. Studies of the composition of small Solar System bodies are fundamental to theories of planet formation. -
The Meteoritical Bulletin, No
Meteoritics & Planetary Science 36, A293–A322 (2001) Available online at http://www.uark.edu/meteor The Meteoritical Bulletin, No. 85, 2001 September JEFFREY N. GROSSMAN1* AND JUTTA ZIPFEL2 1U. S. Geological Survey, Mail Stop 954, Reston, Virginia 20192, USA 2Max Planck Institut für Chemie, Postfach 3060, D-55020 Mainz, Germany *Correspondence author's e-mail address: [email protected] (Received 2001 May 31) Abstract−Meteoritical Bulletin No. 85 lists information for 1376 newly classified meteorites, comprising 658 from Antarctica, 409 from Africa, 265 from Asia (262 of which are from Oman), 31 from North America, 7 from South America, 3 from Australia, and 3 from Europe. Information is provided for 11 falls (Dergaon, Dunbogan, Gujba, Independence, Itqiy, Morávka, Oued el Hadjar, Sayama, Sologne, Valera, and Worden). Noteworthy non-Antarctic specimens include 5 martian meteorites (Dar al Gani 876, Northwest Africa 480 and 817, and Sayh al Uhaymir 051 and 094); 6 lunar meteorites (Dhofar 081, 280, and 287, and Northwest Africa 479, 482, and 773); an ungrouped enstatite-rich meteorite (Itqiy); a Bencubbin-like meteorite (Gujba); 9 iron meteorites; and a wide variety of other interesting stony meteorites, including CH, CK, CM, CO, CR, CV, R, enstatite, and unequilibrated ordinary chondrites, primitive achondrites, HED achondrites, and ureilites. INTRODUCTION ANSMET meteorites (657 meteorites) The Meteoritical Bulletin is a compilation of announcements by Antarctica the Meteoritical Society's Meteorite Nomenclature Committee of Found 1996–2000 newly described and classified meteorites. Additional information Appendix 1 brings up-to-date the list of officially announced about meteorites listed in the Meteoritical Bulletin and the newly meteorites from the U.S. -
Minerals in Meteorites
APPENDIX 1 Minerals in Meteorites Minerals make up the hard parts of our world and the Solar System. They are the building blocks of all rocks and all meteorites. Approximately 4,000 minerals have been identified so far, and of these, ~280 are found in meteorites. In 1802 only three minerals had been identified in meteorites. But beginning in the 1960s when only 40–50 minerals were known in meteorites, the discovery rate greatly increased due to impressive new analytic tools and techniques. In addition, an increasing number of different meteorites with new minerals were being discovered. What is a mineral? The International Mineralogical Association defines a mineral as a chemical element or chemical compound that is normally crystalline and that has been formed as a result of geological process. Earth has an enormously wide range of geologic processes that have allowed nearly all the naturally occurring chemical elements to participate in making minerals. A limited range of processes and some very unearthly processes formed the minerals of meteorites in the earliest history of our solar system. The abundance of chemical elements in the early solar system follows a general pattern: the lighter elements are most abundant, and the heavier elements are least abundant. The miner- als made from these elements follow roughly the same pattern; the most abundant minerals are composed of the lighter elements. Table A.1 shows the 18 most abundant elements in the solar system. It seems amazing that the abundant minerals of meteorites are composed of only eight or so of these elements: oxygen (O), silicon (Si), magnesium (Mg), iron (Fe), aluminum (Al), calcium (Ca), sodium (Na) and potas- sium (K). -
CONTENTS – a Through B
67th Annual Meteoritical Society Meeting (2004) alpha_a-b.pdf CONTENTS – A through B A New Method for the Extraction of the Metal Particles of Ordinary Chondrites: Application to the Al Kidirate (H6) and New Halfa (L4) Meteorites Y. A. Abdu............................................................................................................................................... 5033 Geophysical Signature of Serra Da Cangalha Impact Crater, Brazil A. A. Abraham, J. M. Flexor, and S. L. Fontes....................................................................................... 5167 Characterization of Matrix in the EET92042 CR2 Carbonaceous Chondrite: Insights into Textural and Mineralogical Heterogeneity N. M. Abreu and A. J. Brearley .............................................................................................................. 5178 Mass Fractionation of Fe and Ni Isotopes in Metal in Hammadah Al Hamrah 237 C. M. O’D. Alexander and R. H. Hewins ............................................................................................... 5080 Monocarboxilic Acids Analyse in Murchison Meteorite Using Solid Phase Microextraction (SPME) M. R. Alexandre, Y. Huang, Y. Wang, M. Fuller, and S. Pizzarello....................................................... 5082 Isotopic Study of Presolar Graphite in the KFC1 Separate from the Murchison Meteorite S. Amari, E. Zinner, and R. S. Lewis ...................................................................................................... 5152 The Poty Quarry Conglomeratic Bed: