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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. -
Meteorites on Mars Observed with the Mars Exploration Rovers C
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 113, E06S22, doi:10.1029/2007JE002990, 2008 Meteorites on Mars observed with the Mars Exploration Rovers C. Schro¨der,1 D. S. Rodionov,2,3 T. J. McCoy,4 B. L. Jolliff,5 R. Gellert,6 L. R. Nittler,7 W. H. Farrand,8 J. R. Johnson,9 S. W. Ruff,10 J. W. Ashley,10 D. W. Mittlefehldt,1 K. E. Herkenhoff,9 I. Fleischer,2 A. F. C. Haldemann,11 G. Klingelho¨fer,2 D. W. Ming,1 R. V. Morris,1 P. A. de Souza Jr.,12 S. W. Squyres,13 C. Weitz,14 A. S. Yen,15 J. Zipfel,16 and T. Economou17 Received 14 August 2007; revised 9 November 2007; accepted 21 December 2007; published 18 April 2008. [1] Reduced weathering rates due to the lack of liquid water and significantly greater typical surface ages should result in a higher density of meteorites on the surface of Mars compared to Earth. Several meteorites were identified among the rocks investigated during Opportunity’s traverse across the sandy Meridiani plains. Heat Shield Rock is a IAB iron meteorite and has been officially recognized as ‘‘Meridiani Planum.’’ Barberton is olivine-rich and contains metallic Fe in the form of kamacite, suggesting a meteoritic origin. It is chemically most consistent with a mesosiderite silicate clast. Santa Catarina is a brecciated rock with a chemical and mineralogical composition similar to Barberton. Barberton, Santa Catarina, and cobbles adjacent to Santa Catarina may be part of a strewn field. Spirit observed two probable iron meteorites from its Winter Haven location in the Columbia Hills in Gusev Crater. -
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. -
High Survivability of Micrometeorites on Mars: Sites with Enhanced Availability of Limiting Nutrients
RESEARCH ARTICLE High Survivability of Micrometeorites on Mars: Sites With 10.1029/2019JE006005 Enhanced Availability of Limiting Nutrients Key Points: Andrew G. Tomkins1 , Matthew J. Genge2,3 , Alastair W. Tait1,4 , Sarah L. Alkemade1, • Micrometeorites are predicted to be 1 1 5 far more abundant on Mars than on Andrew D. Langendam , Prudence P. Perry , and Siobhan A. Wilson Earth 1 2 • Micrometeorites are concentrated in School of Earth, Atmosphere and Environment, Melbourne, Victoria, Australia, Impact and Astromaterials Research the residue of aeolian sediment Centre, Department of Earth Science and Engineering, Imperial College London, London, UK, 3Department of removal, such as at bedrock cracks Mineralogy, The Natural History Museum, London, UK, 4Department of Biological and Environmental Sciences, and gravel accumulations University of Stirling, Scotland, UK, 5Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, • Micrometeorite accumulation sites are enriched in key nutrients for Alberta, Canada primitive microbes: reduced phosphorus, sulfur, and iron Abstract NASA's strategy in exploring Mars has been to follow the water, because water is essential for life, and it has been found that there are many locations where there was once liquid water on the surface. Now perhaps, to narrow down the search for life on a barren basalt‐dominated surface, there needs to be a Correspondence to: A. G. Tomkins, refocusing to a strategy of “follow the nutrients.” Here we model the entry of metallic micrometeoroids [email protected] through the Martian atmosphere, and investigate variations in micrometeorite abundance at an analogue site on the Nullarbor Plain in Australia, to determine where the common limiting nutrients available in Citation: these (e.g., P, S, Fe) become concentrated on the surface of Mars. -
EPSC2010-345, 2010 European Planetary Science Congress 2010 C Author(S) 2010
EPSC Abstracts Vol. 5, EPSC2010-345, 2010 European Planetary Science Congress 2010 c Author(s) 2010 Study of non-equivalent Fe positions in some extraterrestrial minerals using Mössbauer spectroscopy with a high velocity resolution M.I. Oshtrakh (1), V.I. Grokhovsky (1), M.Yu. Larionov (1), D.G. Patrusheva (1), E.V. Petrova (1), V.A. Semionkin (1,2) (1) Faculty of Physical Techniques and Devices for Quality Control and (2) Faculty of Experimental Physics, Ural State Technical University – UPI, Ekaterinburg, 620002, Russian Federation. E-mail: [email protected]. Abstract phosphides extracted from iron meteorite. Study of extraterrestrial minerals with non-equivalent 2. Materials and Methods Fe positions such as the M1 and M2 sites in olivine and pyroxenes in ordinary chondrites, the M1 and Samples of Saratov L4, Mount Tazerzait L5, Tsarev L5, M2 sites in olivines from pallasites and the M1, M2 Farmington L5, Mbale L5/6, Kunashak L6, Zubkovsky and M3 sites in iron nickel phosphides from iron L6, Ochansk H4, Richardton H5, Vengerovo H5, meteorites was performed using Mössbauer Zvonkov H6 were prepared as powders for Mössbauer measurements with effective thickness of about 10 mg spectroscopy with a high velocity resolution. 2 Obtained differences were analyzed in order to Fe/cm . Samples of olivine extracted from Omolon PMG and Seymchan PMG were prepared as powders characterize these minerals. with effective thickness of about 6 mg Fe/cm2. Samples of schreibersite and rhabdites extracted from Sikhote- 1. Introduction Alin IIAB iron meteorite mechanically and electrochemically, respectively, were prepared with A number of extraterrestrial iron bearing minerals effective thickness of about 5–6 mg Fe/cm2. -
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. -
THE Hf-W ISOTOPIC SYSTEM and the ORIGIN of the EARTH and MOON
18 Mar 2005 11:55 AR AR233-EA33-18.tex XMLPublishSM(2004/02/24) P1: KUV 10.1146/annurev.earth.33.092203.122614 Annu. Rev. Earth Planet. Sci. 2005. 33:531–70 doi: 10.1146/annurev.earth.33.092203.122614 Copyright c 2005 by Annual Reviews. All rights reserved First published online as a Review in Advance on February 1, 2005 THE Hf-W ISOTOPIC SYSTEM AND THE ORIGIN OF THE EARTH AND MOON Stein B. Jacobsen Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138; email: [email protected] KeyWords accretion, tungsten, isotopes, chronometer, core formation ■ Abstract The Earth has a radiogenic W-isotopic composition compared to chon- drites, demonstrating that it formed while 182Hf (half-life 9 Myr) was extant in Earth and decaying to 182W. This implies that Earth underwent early and rapid accretion and core formation, with most of the accumulation occurring in ∼10 Myr, and concluding approximately 30 Myr after the origin of the Solar System. The Hf-W data for lunar samples can be reconciled with a major Moon-forming impact that terminated the ter- restrial accretion process ∼30 Myr after the origin of the Solar System. The suggestion that the proto-Earth to impactor mass ratio was 7:3 and occurred during accretion is inconsistent with the W isotope data. The W isotope data is satisfactorily modeled with a Mars-sized impactor on proto-Earth (proto-Earth to impactor ratio of 9:1) to form the Moon at ∼30 Myr. 1. INTRODUCTION The process of terrestrial planet-building probably began when a large population of small bodies (planetesimals) of roughly similar size coagulated into a smaller population of larger bodies. -
Allabogdanite (Fe, Ni)2P
Allabogdanite (Fe, Ni)2P Crystal Data: Orthorhombic. Point Group: 2/m 2/m 2/m. As lamellar crystals to 0.4 mm, flattened on (001) with dominant {001} and probable {110} and {100}; pseudo-monoclinic habit. As rounded nodules to 0.5 mm. Twinning: Common, with possible composition plane {110}. Physical Properties: Cleavage: None. Fracture: n.d. Tenacity: Very brittle. Hardness = 5-6 VHN = n.d. D(meas.) = n.d. D(calc.) = 6.729 (Israel); 7.10 (meteorite) Optical Properties: Opaque. Color: Light straw-yellow, steel-gray; creamy white in reflected light. Streak: n.d. Luster: Bright metallic. Optical Class: n.d. Anisotropism: Distinct, light to dark cream. R1-R2: (440) 48.4-37.2, (460) 46.7-36.8, (480) 47.0-37.6, (500) 47.5-38.1, (520) 47.6-38.8, (540) 48.2-39.2, (560) 49.0-39.9, (580) 49.6-40.7, (600) 50.1-41.6, (620) 50.5-41.9, (640) 51.9-43.0, (660) 52.3-44.3, (680) 53.3-45.0, (700) 54.4-46.2 Cell Data: Space Group: Pnma. a = 5.792(7) b = 3.564(4) c = 6.691(8) Z = 4 X-ray Powder Pattern: Onello iron meteorite. 2.238 (100), 2.120 (80), 2.073 (70), 1.884 (50), 1.843 (40), 1.788 (40), 1.774 (40) Chemistry: (1) (2) Fe 57.7 76.24 Ni 20.7 1.64 Co 1.4 0.19 Mo 0.33 P 20.4 21.58 Total 100.2 100.00 (1) Onello iron meteorite; average of nine electron microprobe analyses; corresponds to (Fe1.51Ni0.50Co0.03)Σ=2.04P0.96. -
HILTON Umd 0117E 21218.Pdf
ABSTRACT Title of Dissertation: GENETICS, AGES, AND CHEMICAL COMPOSITIONS OF IRON METEORITES Connor Hilton, Doctor of Philosophy, 2020 Dissertation directed by: Professor Richard Walker, Department of Geology Comparison of genetic isotopic compositions of iron meteorites with metal- silicate segregation ages suggests that the isotopic composition of the NC reservoir changed with time. By contrast, no such age-linked changes in the genetic isotopic compositions of iron meteorites from the CC reservoir are observed. Results of comparing bulk planetesimal genetic isotopic compositions with bulk planetesimal siderophile element chemical characteristics indicate that the processes responsible for isotopic heterogeneity in the early Solar System are not discerned by the siderophile element chemical characteristics of planetesimals. Iron meteorite parent bodies from the CC reservoir typically have smaller relative cores and a greater proportion of the Fe content in the mantle, consistent with the CC reservoir being a more oxidized environment, such as the outer Solar System, compared to the NC reservoir. The chemical characteristics of iron meteorite parent bodies, including bulk core FeS/Fe ratios and oxidation states, may form relationships with core formation ages, but whether these characteristics can account for potential differences in the formation ages of NC- and CC-type parent bodies presently cannot be constrained. GENETICS, AGES, AND CHEMICAL COMPOSITIONS OF IRON METEORITES by Connor D. Hilton Dissertation submitted to the Faculty of the Graduate School of the University of Maryland, College Park, in partial fulfillment of the requirements for the degree of Doctor of Philosophy 2020 Advisory Committee: Professor Richard J. Walker, Chair Associate Professor Ricardo D. Arevalo Research Scientist Richard D. -
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. -
Texture, Chemical Composition and Genesis of Schreibersite in Iron Meteorite
Title Texture, Chemical Composition and Genesis of Schreibersite in Iron Meteorite Author(s) Yoshikawa, Masahide; Matsueda, Hiroharu Citation 北海道大学理学部紀要, 23(2), 255-280 Issue Date 1992-08 Doc URL http://hdl.handle.net/2115/36782 Type bulletin (article) File Information 23-2_p255-280.pdf Instructions for use Hokkaido University Collection of Scholarly and Academic Papers : HUSCAP Jour. Fac. Sci ., Hokkaido Univ., Ser. IV, vol. 23, no. 2, Aug., 1992. pp. 255 -280 TEXTURE, CHEMICAL COMPOSITION AND GENESIS OF SCHREIBERSITE IN IRON METEORITE by Masahide Yoshikawa* and Hiroharu Matsueda (with 13 text-figures, 9 tables and 3 plates) Abstract Thirteen iron meteorites composed of Hexahedrite, Octahedrite and Ataxite were investigated to estimate their cooling history and origin. They are mainly composed of Fe-Ni metals (kamacite and taenite) with smaller amounts of schreibersite (Fe, Ni)3P and sulfides (troilite and sphalerite) . Schreibersite occurs an idiomorphic and xenomorphic crystals and its mode of occurrence is variable in iron meteorites. Xenomorphic schreibersite is subdivided into 6 types on the basis of their textures and relationships with coexisting minerals. Chemical composition of schreibersite varies from 20 to 40 atom. % Ni with textural types among some iron meteorites with different bulk chemical compositions and even in the same meteorite (e. g. Canyon Diablo), while it does not vary so clear with textural types in ALH - 77263. Schreibersite seems to maintain a local equilibrium with coexisting metal phases. Based on the Fe- Ni- P phase diagram, it is estimated that xenomorphic and coarse-grained schreibersite in Y- 75031 and in DRPA 7S007 were crystallized from stability field of taenite and schreibersite at about SOO°C under rapid diffusion conditions.