Occurrence of Carbides and Graphite in Iron Meteorites and Origin of C-Rich Irons
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Handbook of Iron Meteorites, Volume 3
Sierra Blanca - Sierra Gorda 1119 ing that created an incipient recrystallization and a few COLLECTIONS other anomalous features in Sierra Blanca. Washington (17 .3 kg), Ferry Building, San Francisco (about 7 kg), Chicago (550 g), New York (315 g), Ann Arbor (165 g). The original mass evidently weighed at least Sierra Gorda, Antofagasta, Chile 26 kg. 22°54's, 69°21 'w Hexahedrite, H. Single crystal larger than 14 em. Decorated Neu DESCRIPTION mann bands. HV 205± 15. According to Roy S. Clarke (personal communication) Group IIA . 5.48% Ni, 0.5 3% Co, 0.23% P, 61 ppm Ga, 170 ppm Ge, the main mass now weighs 16.3 kg and measures 22 x 15 x 43 ppm Ir. 13 em. A large end piece of 7 kg and several slices have been removed, leaving a cut surface of 17 x 10 em. The mass has HISTORY a relatively smooth domed surface (22 x 15 em) overlying a A mass was found at the coordinates given above, on concave surface with irregular depressions, from a few em the railway between Calama and Antofagasta, close to to 8 em in length. There is a series of what appears to be Sierra Gorda, the location of a silver mine (E.P. Henderson chisel marks around the center of the domed surface over 1939; as quoted by Hey 1966: 448). Henderson (1941a) an area of 6 x 7 em. Other small areas on the edges of the gave slightly different coordinates and an analysis; but since specimen could also be the result of hammering; but the he assumed Sierra Gorda to be just another of the North damage is only superficial, and artificial reheating has not Chilean hexahedrites, no further description was given. -
THE American Museum Journal
T ///^7; >jVvvscu/n o/ 1869 THE LIBRARY THE American Museum Journal VOLUME VII, 1907 NEW YORK: PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY 1907 Committee of Publication EDMUND OTIS HOVF.Y, Ediior. FRANK M. ( IIAPMAN ] LOUIS P. GHATACAP \ .l<lris-on/ linanl WILLIAM K. GREGOIlvJ THE AMERICAN MUSEUM OF NATURAL HISTORY. 77th Street and Central Park West, New York. OFFICERS AND COMMITTEES PRESIDEXT MORRIS K. JESUP FIRST VICE-PRESIDENT SECOND VICE-PRESIDENT J. PIERPONT MORGAN HENRY F. OSBORN TREASURER SECRETARY CHARLES LANIER J. HAMPDEN ROBB ASSISTANT SECRETARY AND DIRECTOR ASSISTANT TREASURER HERMON C. BUMPUS GEORGE H. SHERWOOD BOARD OF TRUSTEES Class of 1907 D. O. :\IILLS ALBERT S. BICKMORE ARCHIBALD ROGERS CORNELIUS C. CUYLER ADRIAN ISELIN, Jr. Class of 1908 H. o. have:\ieyer Frederick e. hyde A. I). JUHJJAIU) GEORCiE S. BOWDOIN (TEVELANl) H. DOIXJE Class of 1909 MORRIS K. JESUP J. PIERPONT MORGAN JOSEPH H. CHOATE GEORGE G. HAVEN HENRY F. OSBORN Class of 1910 J. HAMPDEN ROBB PERCY R. PYNE ARTHUR CURTISS JAMES Class of 1911 CHARLES LANIER WILLIAISI ROCKEFELLER ANSON W. HARD GUSTAV E. KISSEL SETH LOW Scientific Staff DIRECTOR Hermon C. Bumpus, Ph.D., Sc. D. DEPARTMENT OF PUBLIC INSTRUCTION Prof. Albert S. Bickmore, B. S., Ph.D., LL.D., Curator Emeritus George H. Shehwood, A.B., A.M., Curator DEPARTMENT OF GEOLOGY AND INVERTEBRATE PALEONTOLOGY Prof. R. P. Whitfield, A.M., Curator Edmund Otis Hovey, A.B., Ph.D., Associate Curator DEPARTMENT OF MAMMALOGY AND ORNITHOLOGY Prof. J. A. Allen, Ph.D., Curator Frank M. Chapman, Associate Curator DEPARTMENT OF VERTEBRATE PALAEONTOLOGY Prof. -
Meteorites from the Lut Desert (Iran)
Meteorites from the Lut Desert (Iran) Hamed Pourkhorsandi, Jérôme Gattacceca, Pierre Rochette, Massimo d’Orazio, Hojat Kamali, Roberto Avillez, Sonia Letichevsky, Morteza Djamali, Hassan Mirnejad, Vinciane Debaille, et al. To cite this version: Hamed Pourkhorsandi, Jérôme Gattacceca, Pierre Rochette, Massimo d’Orazio, Hojat Kamali, et al.. Meteorites from the Lut Desert (Iran). Meteoritics and Planetary Science, Wiley, 2019, 54 (8), pp.1737-1763. 10.1111/maps.13311. hal-02144596 HAL Id: hal-02144596 https://hal-amu.archives-ouvertes.fr/hal-02144596 Submitted on 31 May 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution - NonCommercial - ShareAlike| 4.0 International License doi: 10.1111/maps.13311 Meteorites from the Lut Desert (Iran) Hamed POURKHORSANDI 1,2*,Jerome^ GATTACCECA 1, Pierre ROCHETTE 1, Massimo D’ORAZIO3, Hojat KAMALI4, Roberto de AVILLEZ5, Sonia LETICHEVSKY5, Morteza DJAMALI6, Hassan MIRNEJAD7, Vinciane DEBAILLE2, and A. J. Timothy JULL8 1Aix Marseille Universite, CNRS, IRD, Coll France, INRA, CEREGE, Aix-en-Provence, France 2Laboratoire G-Time, Universite Libre de Bruxelles, CP 160/02, 50, Av. F.D. Roosevelt, 1050 Brussels, Belgium 3Dipartimento di Scienze della Terra, Universita di Pisa, Via S. -
Handbook of Iron Meteorites, Volume 2 (Canyon Diablo, Part 2)
Canyon Diablo 395 The primary structure is as before. However, the kamacite has been briefly reheated above 600° C and has recrystallized throughout the sample. The new grains are unequilibrated, serrated and have hardnesses of 145-210. The previous Neumann bands are still plainly visible , and so are the old subboundaries because the original precipitates delineate their locations. The schreibersite and cohenite crystals are still monocrystalline, and there are no reaction rims around them. The troilite is micromelted , usually to a somewhat larger extent than is present in I-III. Severe shear zones, 100-200 J1 wide , cross the entire specimens. They are wavy, fan out, coalesce again , and may displace taenite, plessite and minerals several millimeters. The present exterior surfaces of the slugs and wedge-shaped masses have no doubt been produced in a similar fashion by shear-rupture and have later become corroded. Figure 469. Canyon Diablo (Copenhagen no. 18463). Shock The taenite rims and lamellae are dirty-brownish, with annealed stage VI . Typical matte structure, with some co henite crystals to the right. Etched. Scale bar 2 mm. low hardnesses, 160-200, due to annealing. In crossed Nicols the taenite displays an unusual sheen from many small crystals, each 5-10 J1 across. This kind of material is believed to represent shock annealed fragments of the impacting main body. Since the fragments have not had a very long flight through the atmosphere, well developed fusion crusts and heat-affected rim zones are not expected to be present. The energy responsible for bulk reheating of the small masses to about 600° C is believed to have come from the conversion of kinetic to heat energy during the impact and fragmentation. -
Evolution of Asteroidal Cores 747
Chabot and Haack: Evolution of Asteroidal Cores 747 Evolution of Asteroidal Cores N. L. Chabot The Johns Hopkins Applied Physics Laboratory H. Haack University of Copenhagen Magmatic iron meteorites provide the opportunity to study the central metallic cores of aster- oid-sized parent bodies. Samples from at least 11, and possibly as many as 60, different cores are currently believed to be present in our meteorite collections. The cores crystallized within 100 m.y. of each other, and the presence of signatures from short-lived isotopes indicates that the crystallization occurred early in the history of the solar system. Cooling rates are generally consistent with a core origin for many of the iron meteorite groups, and the most current cooling rates suggest that cores formed in asteroids with radii of 3–100 km. The physical process of core crystallization in an asteroid-sized body could be quite different than in Earth, with core crystallization probably initiated by dendrites growing deep into the core from the base of the mantle. Utilizing experimental partitioning values, fractional crystallization models have ex- amined possible processes active during the solidification of asteroidal cores, such as dendritic crystallization, assimilation of new material during crystallization, incomplete mixing in the molten core, the onset of liquid immiscibility, and the trapping of melt during crystallization. 1. INTRODUCTION ture of the metal and the presence of secondary minerals, are also considered (Scott and Wasson, 1975). In the first From Mercury to the moons of the outer solar system, attempt to classify iron meteorites, groups I–IV were de- central metallic cores are common in the planetary bodies fined on the basis of their Ga and Ge concentrations. -
The Tawallah Valley Meteorite. General Description. the Microstructure.Records of the Australian Museum 21(1): 1–8, Plates I–Ii
AUSTRALIAN MUSEUM SCIENTIFIC PUBLICATIONS Hodge-Smith, T., and A. B. Edwards, 1941. The Tawallah Valley meteorite. General description. The Microstructure.Records of the Australian Museum 21(1): 1–8, plates i–ii. [4 July 1941]. doi:10.3853/j.0067-1975.21.1941.518 ISSN 0067-1975 Published by the Australian Museum, Sydney nature culture discover Australian Museum science is freely accessible online at http://publications.australianmuseum.net.au 6 College Street, Sydney NSW 2010, Australia THE TAW ALLAH VALLEY METEORITE. General Description. By T. HODGE-SMI'l'H, The Australian Museum. The Microstructure. By A. B. EDWARDS, Ph.D., D.I.C.,* Research Officer, Mineragraphy Branch, Council for Scientific and Industrial Research. (Plates i-ii and Figures 1-2.) General Description. Little information is available about the finding of this meteorite. Mr. Heathcock, Constable-in-Charge of the Borroloola Police Station, Northern Territory, informed me in April, 1939, that it had been in the Police Station for eighteen months or more. It was found by Mr. Condon, presumably some time in 1937. The weight of the iron as received was 75·75 kg. (167 lb.). A small piece had been cut off, but its weight probably did not exceed 200 grammes. The main mass weighing 39·35 kg. (86i lb.) is in the collection of the Geological Survey, Department of the Interior, Canberra. A portion weighing 30·16 kg. (66~ lb.) and five pieces together weighing 1·67 kg. are in the collection of the Australian Museum, and a slice weighing 453 grammes is in the Museum of the Geology Department, the University of Melbourne. -
ELEMENTAL ABUNDANCES in the SILICATE PHASE of PALLASITIC METEORITES Redacted for Privacy Abstract Approved: Roman A
AN ABSTRACT OF THE THESIS OF THURMAN DALE COOPER for theMASTER OF SCIENCE (Name) (Degree) in CHEMISTRY presented on June 1, 1973 (Major) (Date) Title: ELEMENTAL ABUNDANCES IN THE SILICATE PHASE OF PALLASITIC METEORITES Redacted for privacy Abstract approved: Roman A. Schmitt The silicate phases of 11 pallasites were analyzed instrumen- tally to determine the concentrations of some major, minor, and trace elements.The silicate phases were found to contain about 98% olivine with 1 to 2% accessory minerals such as lawrencite, schreibersite, troilite, chromite, and farringtonite present.The trace element concentrations, except Sc and Mn, were found to be extremely low and were found primarily in the accessory phases rather than in the pure olivine.An unusual bimodal Mn distribution was noted in the pallasites, and Eagle Station had a chondritic nor- malized REE pattern enrichedin the heavy REE. The silicate phases of pallasites and mesosiderites were shown to be sufficiently diverse in origin such that separate classifications are entirely justified. APPROVED: Redacted for privacy Professor of Chemistry in charge of major Redacted for privacy Chairman of Department of Chemistry Redacted for privacy Dean of Graduate School Date thesis is presented June 1,1973 Typed by Opal Grossnicklaus for Thurman Dale Cooper Elemental Abundances in the Silicate Phase of Pallasitic Meteorites by Thurman Dale Cooper A THESIS submitted to Oregon State University in partial fulfillment of the requirements for the degree of Master of Science June 1974 ACKNOWLEDGMENTS The author wishes to express his gratitude to Prof. Roman A. Schmitt for his guidance, suggestions, discussions, and thoughtful- ness which have served as an inspiration. -
N Arieuican%Mllsellm
n ARieuican%Mllsellm PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK 24, N.Y. NUMBER 2I63 DECEMBER I9, I963 The Pallasites BY BRIAN MASON' INTRODUCTION The pallasites are a comparatively rare type of meteorite, but are remarkable in several respects. Historically, it was a pallasite for which an extraterrestrial origin was first postulated because of its unique compositional and structural features. The Krasnoyarsk pallasite was discovered in 1749 about 150 miles south of Krasnoyarsk, and seen by P. S. Pallas in 1772, who recognized these unique features and arranged for its removal to the Academy of Sciences in St. Petersburg. Chladni (1794) examined it and concluded it must have come from beyond the earth, at a time when the scientific community did not accept the reality of stones falling from the sky. Compositionally, the combination of olivine and nickel-iron in subequal amounts clearly distinguishes the pallasites from all other groups of meteorites, and the remarkable juxtaposition of a comparatively light silicate mineral and heavy metal poses a nice problem of origin. Several theories of the internal structure of the earth have postulated the presence of a pallasitic layer to account for the geophysical data. No apology is therefore required for an attempt to provide a comprehensive account of this remarkable group of meteorites. Some 40 pallasites are known, of which only two, Marjalahti and Zaisho, were seen to fall (table 1). Of these, some may be portions of a single meteorite. It has been suggested that the pallasite found in Indian mounds at Anderson, Ohio, may be fragments of the Brenham meteorite, I Chairman, Department of Mineralogy, the American Museum of Natural History. -
'San Juan', a New Mass of the Campo Del Cielo Meteorite Shower
‘San Juan’, a new mass of the Campo del Cielo meteorite shower Marcela Eliana SAAVEDRA1, María Eugenia VARELA1, Andrew J. CAMPBELL 2 and Dan TOPA 3 1Instituto de Ciencias Astronómicas de la Tierra y del Espacio (ICATE)-CONICET, San Juan, Argentina. 2Deptartment of the Geophysical Sciences, University of Chicago, , Chicago, USA. 3Central Research Laboratories, Natural History Museum, , Vienna, Austria. Email: [email protected] Editor: Diego A. Kietzmann Recibido: 19 de marzo de 2021 Aceptado: 15 de junio de 2021 Disponible online: 15 de junio de 2021 ABSTRACT Petrographic and chemical (major, minor and trace element) studies of silicate inclusions and metal from the San Juan A and B samples revealed that they are new masses belonging to the Campo del Cielo IAB iron meteorite shower. These masses must have being transported from the large strewn field in the Chaco and Santiago del Estero Provinces to the surroundings of San Juan city, where they have being recover in the year 2000. The sizes of the two masses of San Juan, collected 770 km SW from Santiago del Estero, is in agreement with the previously suggested anthropic hypothesis for the transport of Campo del Cielo. Keywords: IAB iron meteorites, Campo del Cielo meteorite, San Juan meteorite. RESUMEN San Juan, una nueva masa de la lluvia de meteoritos de Campo del Cielo Estudios petrográficos y químicos (elementos mayores, menores y trazas) de inclusiones de silicatos y de metal de las muestras A y B de San Juan, reveló que son nuevas masas que pertenecen a la lluvia de meteoritos de Campo del Cielo. -
Cohenite in Chondrites: Further Support for a Shock- Heating Origin L
76th Annual Meteoritical Society Meeting (2013) 5145.pdf Cohenite in Chondrites: Further Support for a Shock- Heating Origin L. Likkel1, A.M. Ruzicka2, M. Hutson2, K. Schepker2, and T.R. Yeager1. 1University of Wisconsin–Eau Claire, Department of Physics and Astronomy. E-mail: [email protected]. 2Cascadia Meteorite Laboratory, Portland State University, Oregon, USA. Introduction: The iron-nickel carbide cohenite [(Fe,Ni)3C] is mainly known from iron meteorites but has been found also in some chondrites. It was suggested that cohenite formed in some chondrites by a process of shock-induced contact metamorphism involving heating by adjacent shock melts [1]. Methods: Two meteorite thin sections were chosen for inves- tigation including NWA5964 (CML0175-4-3), an L3-6 chondrite known to have cohenite and containing a large shock melt region [1]. Another sample in which we identified cohenite was select- ed, Buck Mountain Wash (CML0236-3A), an H3-6 chondrite with a smaller shock melt region [2, 3]. We used reflected light optical microscopy to locate each co- henite grain in the thin sections to determine whether cohenite is spatially related to shock melt areas. SEM was used to confirm that the mineral identified as cohenite was not schreibersite, which appears nearly identical to cohenite in reflected light. Results: Shock melt covers most of CML0175-4-3, and some of the adjacent unmelted chondrite host appears to be darkened. Over 50 occurrences of cohenite were found in the sample, locat- ed preferentially at the edge of the melt and excluded from the small areas where the host remained undarkened. -
3D Laser Imaging and Modeling of Iron Meteorites and Tektites
3D laser imaging and modeling of iron meteorites and tektites by Christopher A. Fry A thesis submitted to the Faculty of Graduate and Postdoctoral Affairs in partial fulfillment of the requirements for the degree of Master of Science in Earth Science Carleton University Ottawa, Ontario ©2013, Christopher Fry ii Abstract 3D laser imaging is a non-destructive method devised to calculate bulk density by creating volumetrically accurate computer models of hand samples. The focus of this research was to streamline the imaging process and to mitigate any potential errors. 3D laser imaging captured with great detail (30 voxel/mm2) surficial features of the samples, such as regmaglypts, pits and cut faces. Densities from 41 iron meteorites and 9 splash-form Australasian tektites are reported here. The laser-derived densities of iron meteorites range from 6.98 to 7.93 g/cm3. Several suites of meteorites were studied and are somewhat heterogeneous based on an average 2.7% variation in inter-fragment density. Density decreases with terrestrial age due to weathering. The tektites have an average laser-derived density of 2.41+0.11g/cm3. For comparison purposes, the Archimedean bead method was also used to determine density. This method was more effective for tektites than for iron meteorites. iii Acknowledgements A M.Sc. thesis is a large undertaking that cannot be completed alone. There are several individuals who contributed significantly to this project. I thank Dr. Claire Samson, my supervisor, without whom this thesis would not have been possible. Her guidance and encouragement is largely the reason that this project was completed. -
The Formation of the Widmanstätten Structure in Meteorites
Meteoritics & Planetary Science 40, Nr 2, 239–253 (2005) Abstract available online at http://meteoritics.org The formation of the Widmanstätten structure in meteorites J. YANG* and J. I. GOLDSTEIN Department of Mechanical and Industrial Engineering, College of Engineering, University of Massachusetts, Amherst, Massachusetts 01003, USA *Corresponding author. E-mail: [email protected] (Received 16 October 2003; revision accepted 13 November 2004) Abstract–We have evaluated various mechanisms proposed for the formation of the Widmanstätten pattern in iron meteorites and propose a new mechanism for low P meteoritic metal. These mechanisms can also be used to explain how the metallic microstructures developed in chondrites and stony-iron meteorites. The Widmanstätten pattern in high P iron meteorites forms when meteorites enter the three- phase field α + γ + Ph via cooling from the γ + Ph field. The Widmanstätten pattern in low P iron meteorites forms either at a temperature below the (α + γ)/(α + γ + Ph) boundary or by the decomposition of martensite below the martensite start temperature. The reaction γ → α + γ, which is normally assumed to control the formation of the Widmanstätten pattern, is not applicable to the metal in meteorites. The formation of the Widmanstätten pattern in the vast majority of low P iron meteorites (which belong to chemical groups IAB–IIICD, IIIAB, and IVA) is controlled by mechanisms involving the formation of martensite α2. We propose that the Widmanstätten structure in these meteorites forms by the reaction γ → α2 + γ → α + γ, in which α2 decomposes to the equilibrium α and γ phases during the cooling process.