Roaldite in the iron-meteorite São Julião de Moreira |
| |
| Institution: | 1. Dept 5.1, Federal Institute for Materials, Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany;2. Institut für Geowissenschaften (IGW), Friedrich-Schiller-Universität Jena (FSU), Germany;1. Institut für Geowissenschaften, Universität Kiel, Germany;2. Forschungsinstitut und Naturmuseum Senckenberg, Frankfurt/Main, Germany;1. Institute of Geoscience, Friedrich Schiller University Jena, Carl-Zeiss-Promenade 10, 07745 Jena, Germany;2. Hawai’i Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawai’i at Manoa, HI 96822, USA;1. Natural History Sciences, Hokkaido University, Sapporo 060-0810, Japan;2. Isotope Imaging Laboratory, Creative Research Institution, Hokkaido University, Sapporo 001-0021, Japan;3. UTokyo Organization for Planetary and Space Science (UTOPS), University of Tokyo, Tokyo 113-0033, Japan;4. ISAS/JAXA, Sagamihara, Kanagawa 252-210, Japan;1. UCL/Birkbeck Centre for Planetary Sciences, University College London, Gower St, London, WC1E 6BT, UK;2. Dept. of Earth Sciences, Natural History Museum, Cromwell Rd, London, SW7 5BD, UK;3. Dept. of Earth and Planetary Sciences, Birkbeck University of London, Malet St., London, WC1E 7HX, UK;4. Lunar and Planetary Institute/USRA, 3600 Bay Area Blvd, Houston, TX 77058, USA;5. Earth Observatory of Singapore & Facility for Analysis, Characterisation, Testing, and Simulation, Nanyang Technological University, 639798, Singapore;6. Astromaterials Research Office, NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058, USA;7. Department of Earth, Ocean and Atmospheric, Science & National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Drive, Tallahassee, FL 32310, USA;1. Dept. of Mineral Sciences, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20560-0119, USA;2. Science Matters Consulting, LLC, Washington, DC, 20016, USA;3. School of Earth and Planetary Sciences, Curtin University, Bentley, WA, 6102, Australia;4. Center for Meteorite Studies, School of Earth and Space Exploration, Arizona State University, Tempe, AZ, 85287-1404, USA;1. Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygin St. 19, Moscow, 119991, Russia;2. University of Hawai‘i at Mānoa, 1680 East-West Road, Honolulu, HI, 96822, USA;3. Institute for Dynamics of Geosphere, Russian Academy of Sciences, Moscow, Russia |
| |
| Abstract: | Roaldite – Fe4N – has been identified in the São Julião de Moreira iron meteorite using electron backscatter diffraction (EBSD) and simultaneously acquired energy-dispersive x-ray spectroscopy (EDS). Mean-periodic-number images derived from raw EBSD patterns confirm this phase by an even higher spatial resolution compared to EDS.Roaldite appears in the form of systematically and repetitively aligned plates. Despite the locally heavy plastic deformation, it is shown that the origin of the oriented precipitation of roaldite is linked to the orientation of the kamacite matrix. Roaldite can be considered to be precipitated from kamacite using an inverse Kurdjumov-Sachs (K-S) or Nishiyama-Wassermann (N-W) orientation relationship. A more accurate discrimination is impossible due to the accumulated shock deformation, which blurs the local reference orientation of kamacite. The habit plane of roaldite is found to be {112}R, which is most likely parallel to {120}K of kamacite. Some of the roaldite plates contain two orientation variants which repeatedly alternate. Their misorientation angle is about 12°. |
| |
| Keywords: | Iron meteorite Corrosion Nitride Orientation relationship Plastic deformation |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
