Wangdaodeite, the LiNbO3‐structured high‐pressure polymorph of ilmenite, a new mineral from the Suizhou L6 chondrite

1,2Xiande Xie,3Xiangping Gu,4Hexiong Yang,2Ming Chen,4Kai Li
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.13426]
1Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640 China
2Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou, 510640 China
3School of Geosciences and Info‐Physics, Central South University, Changsha, Hunan, 410083 China
4Department of Geosciences, University of Arizona, 1040 E. 4th Street, Tucson, Arizona, 85721‐0077 USA
5Institute for Materials Microstructure, Central South University, 410083 Changsha, Hunan, PR China
Published by arrangement with John Wiley & Sons

Wangdaodeite, the shock‐induced lithium niobate–structured polymorph of ilmenite, was found in the Suizhou L6 chondrite. It occurs as small irregular particles (2–20 μm in size) inside or adjacent to the shock melt veins. Wangdaodeite coexists in veins with ringwoodite, majorite, and xieite. The chemical formula of wangdaodeite is FeTiO3. The empirical formula is: (Fe0.85Mg0.10Mn0.05)Σ1.00Ti0.99O3, which is similar to that of its host ilmenite. The Raman spectra of wangdaodeite display the bands at 174–179, 273–277, 560–567, 738–743 cm−1, which are different to those for ilmenite. TEM images show that ilmenite is composed of polysynthetic‐twinned crystals while wangdaodeite is composed of random‐oriented nanometric domains sized 20–50 nm. Electron diffraction established wangdaodeite to be trigonal with the lithium niobate structure. Cell parameters are: a = 5.13(1) Å, c = 13.78(1) Å; c/a = 2.69; space group R3c; calculated density = 4.72 g cm−3. The P–T conditions for formation of wangdaodeite were estimated to be 20–24 GPa and >1200 °C. The mineral name was approved by the Commission on New Minerals, Nomenclature, and Classification of the International Mineralogical Association (IMA 2016‐007). The name is for Daode Wang, Professor at the Guangzhou Institute of Geochemistry, Chinese Academy of Sciences.

Application of Mössbauer spectroscopy for classification of ordinary chondrites – different database and different methods

1Gałązka-Friedman, J.,2Woźniak, M.,1Bogusz, P.,1Jakubowska, M.,3Karwowski, Ł.,1Duda, P.
Hyperfine Interactions 241, 20 Link to Article [DOI: 10.1007/s10751-019-1661-0]
1Faculty of Physics, Warsaw University of Technology, Koszykowa 75, Warsaw, 00-662, Poland
2Faculty of Biology, University of Warsaw, Miecznikowa 1, Warszawa, 02-096, Poland
3Faculty of Earth Sciences, University of Silesia in Katowice, ul. Będzińska 60, Sosnowiec, 41-200, Poland

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A Miocene impact ejecta layer in the pelagic Pacific Ocean

1,2,3,4Nozaki, T. et al. (>10)
Scientific Reports 9, 16111 Link to Article [DOI: 10.1038/s41598-019-52709-1]
1Submarine Resources Research Center, Research Institute for Marine Resources Utilization, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka, Kanagawa 237-0061, Japan
2Frontier Research Center for Energy and Resources (FRCER), School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
3Department of Planetology, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
4Ocean Resources Research Center for Next Generation, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan

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Investigation of (micro-)meteoritic materials at the new hard X-ray imaging PUMA beamline for heritage sciences

1Tack, P.,1Bazi, B.,1Vekemans, B.,2Okbinoglu, T.,3Van Maldeghem, F.,3Goderis, S.,2Schöder, S.,1Vincze, L.
Journal of Synchotron Radiation 26, 2033-2039 Link to Article [DOI: 10.1107/S160057751901230X]
1Chemistry, Ghent University, Krijgslaan 281 S12, Ghent, 9000, Belgium
2PUMA Beamline, Synchrotron SOLEIL, Saint-Aubin BP48, Gif-sur-Yvette, F-91192, France
3Analytical-, Environmental- and Geo-chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels, 1000, Belgium

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High‐temperature HCl evolutions from mixtures of perchlorates and chlorides with water‐bearing phases: Implications for the Sample Analysis at Mars (SAM) instrument in Gale crater, Mars

1J.V. Clark,2B. Sutter,3A.C. McAdam,4E.B. Rampe,2P.D. Archer,4D.W. Ming,5R. Navarro‐Gonzalez,3P. Mahaffy,6T.J. Lapen
Journal of Geophysical Research, Planets (in Press) Link to Article [https://doi.org/10.1029/2019JE006173]
1Geocontrols Systems – Jacobs JETS Contract at NASA Johnson Space Center, Houston, TX
2Jacobs JETS Contract at NASA Johnson Space Center, Houston, TX
3NASA Goddard Space Flight Center, Greenbelt, MD
4NASA Johnson Space Center, Houston, TX
5Universidad Nacional Autonoma de Mexico, Mexico City, Mexico
6University of Houston, Houston, TX
Published by arrangement with John Wiley & Sons

Evolved hydrogen chloride (HCl) detected by the Sample Analysis at Mars (SAM) instrument’s evolved gas analysis (EGA) mode on board the Mars Science Laboratory Curiosity rover has been attributed to oxychlorines (i.e., perchlorates and chlorates) or chlorides in Gale crater samples. Previous laboratory EGA studies of oxychlorines have been unable to reproduce the high‐temperature (>600 °C) HCl evolutions observed in most Gale crater samples. The objective of this work was to reproduce these high temperature HCl releases from laboratory mixtures of perchlorates and chlorides with phases that evolve water upon heating. Magnesium and sodium perchlorate and chloride were mixed with saponite, nontronite, and a basaltic glass and analyzed in a laboratory thermal evolved gas analyzer configured to operate similarly to the SAM instrument. Na perchlorate and chloride evolved HCl only when mixed with all three water‐producing phases. Mg perchlorate and chloride evolved a mid‐temperature HCl release (~450‐550 °C) and evolved an additional high‐temperature HCl release (~810‐820 °C) when mixed with saponite. This work demonstrated that chlorides, either originally present or from perchlorate decomposition, evolved high‐temperature HCl when reacting with water from water‐producing phases. The HCl release temperature was dependent on the mixture’s mineralogy and chemical composition. HCl releases detected by SAM were consistent with oxychlorines and/or chlorides in the presence of water‐producing phases. Additionally, this work provided constraints on the presence of oxychlorines or chlorides and their cation‐types, which has implications for past aqueous and diagenetic processes, the potential for past life, and detection of organics by EGA.