Association of silica phases as geothermobarometer for eucrites: Implication for two-stage thermal metamorphism in the eucritic crust

1,2Haruka Ono,3Atsushi Takenouchi,1,4Takashi Mikouchi,3,5Akira Yamaguchi,6,7Masahiro Yasutake,8Akira Miyake,8,9,10Akira Tsuchiyama
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.13664]
1Department of Earth and Planetary Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan
2Planetary Exploration Research Center, Chiba Institute of Technology, 2-17-1, Tsudanuma, Narashino, Chiba, 275-0016 Japan
3National Institute of Polar Research (NIPR), 10-3 Midori-cho, Tachikawa, Tokyo, 190-8518 Japan
4The University Museum, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan
5Department of Polar Science, School of Multidisciplinary Science, SOKENDAI (The Graduate University for Advanced Studies), Tokyo, 190-8518 Japan
6Japan Synchrotron Radiation Research Institute (JASRI), SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198 Japan
7Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577 Japan
8Department of Geology and Mineralogy, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, 606-8502 Japan
9CAS Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (CAS), Guangzhou, 510640 People’s Republic of China
10CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640 People’s Republic of China
Published by arrangement with John Wiley & Sons

Silica mineral is present in different stable polymorphs depending on the temperature and pressure conditions of crystallization. We suggest using silica mineral phases to constrain the thermal history of eucrites. We focused on silica minerals in basaltic clasts of nine non-cumulate eucrites to compare with previously studied cumulate eucrites. Our observations indicate an apparent relationship between thermal metamorphic degrees and silica phase texture in basaltic clasts of non-cumulate eucrites. To reveal complex transformation relations between silica polymorphs in eucrites, we performed cooling experiments (cooling rate: 1 and 0.1 °C h−1) and heating experiments (heating 500 °C for 168 h and 800 °C for 96 h) using eucrites. The cooling experiments show that cristobalite is an initial silica phase crystallized from eucritic magma and transforms to quartz at the cooling rate between 0.1 and 1 °C h−1. Based on the cooling experiments and observations of eucrites, we suggest that a combination of silica minerals varies depending mainly on cooling rates. According to the heating experiments, monoclinic tridymite hardly transforms to other phases at low temperature by short reheating events such as brecciation. Monoclinic tridymite can partially transform to quartz with a “hackle” fracture. We conclude that a reheating event partially transformed monoclinic tridymite to quartz to form aggregates of monoclinic tridymite and quartz with the hackle fracture in eucrites. We suggested that some basaltic clasts in non-cumulate eucrites experienced two-stage thermal metamorphism in the eucritic crust. The first metamorphic event has resulted from burial under lava produced by successive eruptions. Igneous intrusions into the preformed crust may have caused the second metamorphic event. The intrusions heated the deep eucritic crust and induced the transformation from monoclinic tridymite to quartz.

Noble gases in CM carbonaceous chondrites: Effect of parent body aqueous and thermal alteration and cosmic ray exposure ages

1Daniela Krietsch,1Henner Busemann,1My E.I.Riebe,2,3Ashley J.King,4Conel M.O’D. Alexander,1Colin Maden
Geochimica et Cosmochimica Acta (in Press) Link to Article [https://doi.org/10.1016/j.gca.2021.05.050]
1Institute of Geochemistry and Petrology, ETH Zurich, Clausiusstrasse 25, 8092 Zurich, Switzerland
2School of Physical Sciences, The Open University, Milton Keynes MK7 6AA, UK
3Planetary Materials Group, Natural History Museum, London SW7 5BD, UK
4Earth and Planets Laboratory, Carnegie Institution of Washington, 5241 Broad Branch Road, N. W., Washington, DC 20015, USA
Copyright Elsevier

Like most primitive carbonaceous chondrites, the CM chondrites experienced varying degrees of asteroidal aqueous alteration, which may have overprinted pre-accretionary processing. Several aqueous alteration scales for CM chondrites (and other carbonaceous chondrites) have been proposed based on alteration-dependent changes in various petrological and geochemical characteristics. Given the possibility that the intensity of aqueous alteration could be recorded in the primordial noble gas compositions, we test potential correlations between petrologic, geochemical and noble gas characteristics in a detailed study on 39 CM chondrites, including some of the most pristine CM chondrites identified to date, and 4 CM-related carbonaceous chondrites. We mainly compare our noble gas data with the alteration schemes proposed by Alexander et al. (2013) and Howard et al. (2015). In addition to the noble gas analyses, we determined the phyllosilicate fractions of 17 of the CM chondrites using X-ray diffraction (XRD) to complement missing data points in the Howard alteration scheme. The influence of post-hydration thermal modification on noble gases in CM chondrites is investigated by comparison of heated and unheated samples. Cosmic-ray exposure (CRE) ages are determined for all samples in this study as well as for 26 more samples based on CM chondrite literature noble gas data.

The noble gas inventory in CM chondrites represents a mixture of cosmogenic, radiogenic, and abundant primordially trapped noble gases. Additionally, about 50 % of our CM bulk samples contain detectable solar wind (SW), which implies that many but not all CM chondrites are regolith breccias or carry SW from a pre-accretion irradiation phase. Aqueous alteration affects primordial noble gas abundances and elemental and isotopic compositions in CM chondrites. In particular, the process causes loss of an Ar-rich component, different in elemental and isotopic composition to known noble gas components. This component is lost during the early stages of aqueous alteration until complete degassing of its carrier material (possibly upon at least partial destruction) below petrologic type of ∼1.5 on the Howard et al. (2015) scale. Likely, small amounts of Q gases were additionally released by aqueous alteration. Strong thermal modification at >750 °C results in a significant additional loss of noble gases, whereas peak temperatures <500 °C likely have minor effects on the noble gas inventories of CM chondrites. Some of the described trends of noble gas contents and elemental and isotopic ratios in this study are observable across multiple carbonaceous chondrite groups, in particular also the CR chondrites. Hence, these carbonaceous chondrites may have started with similar initial noble gas inventories due to accretion of material from a common reservoir. The CRE ages of most of our CM samples fall within the typical range of <10 Myr previously observed for CM chondrites. A few CM chondrites, however, show longer CRE ages, with the longest CRE age of ∼20 Myr determined for the SW-rich CM Allan Hills (ALH) 85013. The degree of aqueous and thermal alteration is variable among CM chondrites with similar CRE ages.

The Tarda Meteorite: A Window into the Formation of D-Type Asteroids

1Yves Marrocchi,2Guillaume Avice,3Jean-Alix Barrat
The Astrophysical Journal Letters, 913, L9 Link to Article [DOI https://doi.org/10.3847/2041-8213/abfaa3]
1Université de Lorraine, CNRS, CRPG, UMR 7358, Vandœuvre-lès-Nancy, F-54501, France; yvesm@crpg.cnrs-nancy.fr
2Université de Paris, Institut de physique du globe de Paris, CNRS, F-75005 Paris, France
3Université de Brest, CNRS, IRD, Ifremer, LEMAR, F-29280 Plouzané, France

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XAFS and XRD study on Fe, Ni, and Ge in iron meteorite NWA 859

1Shao H.,1Isobe H.,1Kitahara G.,2Fukui H.,1Yoshiasa A.
Physics and Chemistry of Minerals 48, 11 Link to Article [DOI 10.1007/s00269-021-01136-8]
1Department of Earth and Environmental Sciences, Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto, 860-8555, Japan
2Department of Material Science, Graduate School of Material Science, University of Hyogo, Hyogo, 678-1297, Japan

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Synthesis and characterization of Fe(III)-Fe(II)-Mg-Al smectite solid solutions and implications for planetary science

1,2Valerie K. Fox et al. (>10)
American Mineralogist 106, 964–982 Link to Article [DOI: https://doi.org/10.2138/am-2020-7419CCBYNCND]
1California Institute of Technology, 1200 E. California Boulevard, Pasadena, California 91125, U.S.A
2University of Minnesota, John T. Tate Hall, 116 Church Street
SE, Minneapolis, MN 55455-0149, U.S.A.
Copyright: The Mineralogical Society of America

This study demonstrates the synergies and limits of multiple measurement types for the detection
of smectite chemistry and oxidation state on planetary surfaces to infer past geochemical conditions.
Smectite clay minerals are common products of water-rock interactions throughout the solar system,
and their detection and characterization provides important clues about geochemical conditions and past
environments if sufficient information about their composition can be discerned. Here, we synthesize
and report on the spectroscopic properties of a suite of smectite samples that span the intermediate
compositional range between Fe(II), Fe(III), Mg, and Al end-member species using bulk chemical
analyses, X‑ray diffraction, Vis/IR reflectance spectroscopy, UV and green-laser Raman spectroscopy,
and Mössbauer spectroscopy. Our data show that smectite composition and the oxidation state of octahedral Fe can be reliably identified in the near infrared on the basis of combination and fundamental
metal-OH stretching modes between 2.1–2.9 μm, which vary systematically with chemistry. Smectites
dominated by Mg or Fe(III) have spectrally distinct fundamental and combination stretches, whereas
Al-rich and Fe(II)-rich smectites have similar fundamental minima near 2.76 μm, but have distinct
combination M-OH features between 2.24 and 2.36 μm. We show that with expanded spectral libraries that include intermediate composition smectites and both Fe(III) and Fe(II) oxidation states, more
refined characterization of smectites from MIR data is now possible, as the position of the 450 cm–1
absorption shifts systematically with octahedral Fe content, although detailed analysis is best accomplished in concert with other characterization methods. Our data also provide the first Raman spectral
libraries of smectite clays as a function of chemistry, and we demonstrate that Raman spectroscopy
at multiple excitation wavelengths can qualitatively distinguish smectite clays of different structures
and can enhance interpretation by other types of analyses. Our sample set demonstrates how X-ray
diffraction can distinguish between dioctahedral and trioctahedral smectites using either the (02,11) or
(06,33) peaks, but auxiliary information about chemistry and oxidation state aids in specific identifications. Finally, the temperature-dependent isomer shift and quadrupole splitting in Mössbauer data are
insensitive to changes in Fe content but reliability differentiates Fe within the smectite mineral structure.

Widespread Tissintite in Strongly Shock-Lithified Lunar Regolith Breccias

1,2Zhang A.-C.,1,3Jiang Q.-T.,4Tomioka N.,5Guo Y.-J.,1Chen J.-N.,2,6Li Y.,7Sakamoto N.,7,8Yurimoto H.
Geophysical Research Letters 48, e2020GL091554 Link to Article [DOI 10.1029/2020GL091554]
1State Key Laboratory for Mineral Deposits Research, School of Earth Science and Engineering, Nanjing University, Nanjing, China
2CAS Center for Excellence in Comparative Planetology, Hefei, China
3Now at Department of Geology & Geophysics, Yale University, New Haven, United States
4Kochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Nankoku, Japan
5CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, China
6Center for Lunar and Planetary Sciences, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China
7Isotope Imaging Laboratory, Creative Research Institution, Hokkaido University, Sapporo, Japan
8Department of Natural History Sciences, Hokkaido University, Sapporo, Japan

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A high-performance oxygen evolution electrode of nanoporous Ni-based solid solution by simulating natural meteorites

1Hao B.,1Ye Z.,1Xu J.,1Li L.,1Huang J.,1Peng X.,1Li D.,2Jin Z.,3Ma G.
Chemical Engineering Journal 410, 128340 Link to Article [DOI 10.1016/j.cej.2020.128340]
1School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang, 330063, China
2Key Laboratory of Mesoscopic Chemistry of MOE, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
3Global Energy Interconnection Research Institute Co., Ltd, Beijing, 102209, China

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Bjurböle L/LL4 ordinary chondrite properties studied by Raman spectroscopy, X-ray diffraction, magnetization measurements and Mössbauer spectroscopy

1,2Maksimiva, A.A. et al. (>10)
Spectrochimica Acta – Part A: Molecular and Biomolecular SpectroscopyVolume 2485, 119196 Link to Article [DOI
10.1016/j.saa.2020.119196]
1Institute of Physics and Technology, Ural Federal University, Ekaterinburg, 620002, Russian Federation
2The Zavaritsky Institute of Geology and Geochemistry of the Ural Branch of the Russian Academy of Sciences, Ekaterinburg, 620016, Russian Federation

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The Mechanical Properties of Chelyabinsk LL5 Chondrite Under Compression and Tension

1,2Zaytsev D.,3Borodin E.N.,4Dudorov A.E.,1Panfilov P.
Earth, Moon and Planets 125, 2 Link to Article [DOI 10.1007/s11038-021-09539-x]
1Institute of Natural Sciences and Mathematics, Ural Federal University, 620002 Mira str., 19, Ekaterinburg, Russian Federation
2The Institute of High Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences, st. Akademicheskaya, 20, Yekaterinburg, 620137, Russian Federation
3Mechanics and Physics of Solids Research Group, Department of MACE, The University of Manchester, Manchester, M13 9PL, United Kingdom
4Department of Physics, Chelyabinsk State University, 454001 Br. Kashirinykh str., 129, Chelyabinsk, Russian Federation

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EVIDENCE FOR PROTOSOLAR GRAPHENE IN ALLENDE AND QUE 94366 CV3 METEORITES

1,2Chaitanya Giri,2Andrew Steele,3Marc Fries
Planetary and Space Sciences (in Press) Link to Article [https://doi.org/10.1016/j.pss.2021.105267]
1Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo, 152-8550, Japan
2Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, DC, 20015, USA
3Astromaterials Research and Exploration Science Division, NASA Johnson Space Center, Houston, TX, 77058, USA

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