Carbonaceous chondrites—II. Carbonaceous chondrite phyllosilicates and light element geochemistry as indicators of parent body processes and surface conditions

AbstractMeteorite magnetizations can provide rare insight into early Solar System evolution. Such data take on new importance with recognition of the isotopic dichotomy between non-carbonaceous and carbonaceous meteorites, representing distinct inner and outer disk reservoirs, and the likelihood that parent body asteroids were once separated by Jupiter and subsequently mixed. The arrival time of these parent bodies into the main asteroid belt, however, has heretofore been unknown. Herein, we show that weak CV (Vigarano type) and CM (Mighei type) carbonaceous chondrite remanent magnetizations indicate acquisition by the solar wind 4.2 to 4.8 million years after Ca-Al-rich inclusion (CAI) formation at heliocentric distances of ~2–4 AU. These data thus indicate that the CV and CM parent asteroids had arrived near, or within, the orbital range of the present-day asteroid belt from the outer disk isotopic reservoir within the first 5 million years of Solar System history.

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Carbonaceous chondrite meteorites as a record of protoplanetary disk conditions

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319009177 ◽

2019 ◽

Vol 15 (S350) ◽

pp. 135-138

Author(s):

Sara S. Russell ◽

Enrica Bonato ◽

Helena Bates ◽

Ashley J. King ◽

Natasha V. Almeida ◽

...

Keyword(s):

Organic Molecules ◽

Carbonaceous Chondrite ◽

Protoplanetary Disk ◽

Parent Body ◽

Carbonaceous Chondrites ◽

Aqueous Processing ◽

Chondritic Meteorites ◽

Dust Component ◽

Key Features ◽

Complex Organic

AbstractChondritic meteorites, and especially the most volatile-rich chondrites, the carbonaceous chondrites, preserve a record of the solar protoplanetary disk dust component and how it has been changed both in the disk environment itself and in its asteroidal parent body. Here we review some of the key features of carbonaceous chondrites and report some new data on their organics component. These show that the nebula reached temperature of >10000C, but only very locally, to produce chondrules. Most meteoritic material underwent thermal and/or aqueous processing, but some retain delicate nebular components such as complex organic molecules and amorphous silicates.

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Discovery of fossil asteroidal ice in primitive meteorite Acfer 094

Science Advances ◽

10.1126/sciadv.aax5078 ◽

2019 ◽

Vol 5 (11) ◽

pp. eaax5078 ◽

Cited By ~ 1

Author(s):

Megumi Matsumoto ◽

Akira Tsuchiyama ◽

Aiko Nakato ◽

Junya Matsuno ◽

Akira Miyake ◽

...

Keyword(s):

Solar Nebula ◽

Carbonaceous Chondrite ◽

Parent Body ◽

Carbonaceous Chondrites ◽

X Ray ◽

Porous Texture ◽

Fine Grained ◽

X Ray Computed ◽

Source Materials ◽

Insight Into

Carbonaceous chondrites are meteorites believed to preserve our planet’s source materials, but the precise nature of these materials still remains uncertain. To uncover pristine planetary materials, we performed synchrotron radiation–based x-ray computed nanotomography of a primitive carbonaceous chondrite, Acfer 094, and found ultraporous lithology (UPL) widely distributed in a fine-grained matrix. UPLs are porous aggregates of amorphous and crystalline silicates, Fe─Ni sulfides, and organics. The porous texture must have been formed by removal of ice previously filling pore spaces, suggesting that UPLs represent fossils of primordial ice. The ice-bearing UPLs formed through sintering of fluffy icy dust aggregates around the H2O snow line in the solar nebula and were incorporated into the Acfer 094 parent body, providing new insight into asteroid formation by dust agglomeration.

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Discovery of primitive CO2-bearing fluid in an aqueously altered carbonaceous chondrite

Science Advances ◽

10.1126/sciadv.abg9707 ◽

2021 ◽

Vol 7 (17) ◽

pp. eabg9707

Author(s):

Akira Tsuchiyama ◽

Akira Miyake ◽

Satoshi Okuzumi ◽

Akira Kitayama ◽

Jun Kawano ◽

...

Keyword(s):

Solar System ◽

Direct Evidence ◽

Carbonaceous Chondrite ◽

Parent Body ◽

Carbonaceous Chondrites ◽

Hydrous Minerals ◽

X Ray ◽

Transmission Electron ◽

X Ray Computed ◽

Orbital Instability

Water is abundant as solid ice in the solar system and plays important roles in its evolution. Water is preserved in carbonaceous chondrites as hydroxyl and/or H2O molecules in hydrous minerals, but has not been found as liquid. To uncover such liquid, we performed synchrotron-based x-ray computed nanotomography and transmission electron microscopy with a cryo-stage of the aqueously altered carbonaceous chondrite Sutter’s Mill. We discovered CO2-bearing fluid (CO2/H2O > ~0.15) in a nanosized inclusion incorporated into a calcite crystal, appearing as CO2 ice and/or CO2 hydrate at 173 K. This is direct evidence of dynamic evolution of the solar system, requiring the Sutter’s Mill’s parent body to have formed outside the CO2 snow line and later transportation to the inner solar system because of Jupiter’s orbital instability.

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Redistribution of Sr and rare earth elements in the matrices of CV3 carbonaceous chondrites during aqueous alteration in their parent body

Earth Planets and Space ◽

10.1186/s40623-018-0809-5 ◽

2018 ◽

Vol 70 (1) ◽

Cited By ~ 1

Author(s):

Kaori Jogo ◽

Motoo Ito ◽

Tomoki Nakamura ◽

Sachio Kobayashi ◽

Jong Ik Lee

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Parent Body ◽

Carbonaceous Chondrites ◽

Aqueous Alteration

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Machiite, Al2Ti3O9, a new oxide mineral from the Murchison carbonaceous chondrite: A new ultra-refractory phase from the solar nebula

American Mineralogist ◽

10.2138/am-2020-7185 ◽

2020 ◽

Vol 105 (2) ◽

pp. 239-243 ◽

Cited By ~ 1

Author(s):

Alexander N. Krot ◽

Kazuhide Nagashima ◽

George R. Rossman

Keyword(s):

Isotopic Composition ◽

Solar Nebula ◽

Carbonaceous Chondrite ◽

Parent Body ◽

Oxygen Isotopic Composition ◽

New Mineral ◽

Calculated Density ◽

California Institute Of Technology ◽

Oxygen Isotopic ◽

Institute Of Technology

Abstract Machiite (IMA 2016-067), Al2Ti3O9, is a new mineral that occurs as a single euhedral crystal, 4.4 μm in size, in contact with an euhedral corundum grain, 12 μm in size, in a matrix of the Murchison CM2 carbonaceous chondrite. The mean chemical composition of holotype machiite by electron probe microanalysis is (wt%) TiO2 59.75, Al2O3 15.97, Sc2O3 10.29, ZrO2 9.18, Y2O3 2.86, FeO 1.09, CaO 0.44, SiO2 0.20, MgO 0.10, total 99.87, giving rise to an empirical formula (based on 9 oxygen atoms pfu) of (Al1.17Sc0.56Y0.10Ti0.084+Fe0.06Ca0.03Mg0.01)(Ti2.714+Zr0.28Si0.01)O9. The general formula is (Al,Sc)2(Ti4+,Zr)3O9. The end-member formula is Al2Ti3O9. Machiite has the C2/c schreyerite-type structure with a = 17.10 Å, b = 5.03 Å, c = 7.06 Å, β = 107°, V = 581 Å3, and Z = 4, as revealed by electron backscatter diffraction. The calculated density using the measured composition is 4.27 g/cm3. The machiite crystal is highly 16O-depleted relative to the coexisting corundum grain (Δ17O = –0.2 ± 2.4‰ and –24.1 ± 2.6‰, respectively; where Δ17O = δ17O – 0.52 × δ18O). Machiite is a new member of the schreyerite (V2Ti3O9) group and a new Sc,Zr-rich ultrarefractory phase formed in the solar nebula, either by gas-solid condensation or as a result of crystallization from a Ca,Al-rich melt having solar-like oxygen isotopic composition (Δ17O~ –25‰) under high-temperature (~1400–1500 °C) and low-pressure (~10-4–10-5 bar) conditions in the CAI-forming region near the protosun. The currently observed disequilibrium oxygen isotopic composition between machiite and corundum may indicate that machiite subsequently experienced oxygen isotopic exchange with a planetary-like 16O-poor gaseous reservoir either in the solar nebula or on the CM chondrite parent body. The name machiite is in honor of Chi Ma, mineralogist at California Institute of Technology, for his contributions to meteorite mineralogy and discovery of many new minerals representing extreme conditions of formation.

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