scholarly journals A long duration of the 16O-rich reservoir in the solar nebula, as recorded in fine-grained refractory inclusions from the least metamorphosed carbonaceous chondrites

2017 ◽  
Vol 201 ◽  
pp. 103-122 ◽  
Author(s):  
Takayuki Ushikubo ◽  
Travis J. Tenner ◽  
Hajime Hiyagon ◽  
Noriko T. Kita
Keyword(s):  
Solar Nebula ◽  
Carbonaceous Chondrites ◽  
Fine Grained ◽  
Long Duration

Phyllosilicates and other layer-structured materials in stony meteorites

Clay Minerals ◽  
1985 ◽  
Vol 20 (4) ◽  
pp. 415-454 ◽  
Author(s):  
D. J. Barber
Keyword(s):  
Major Part ◽  
Solar Nebula ◽  
Layered Compounds ◽  
Carbonaceous Chondrites ◽  
Aqueous Alteration ◽  
Structured Materials ◽  
Fine Grained ◽  
Current Thinking ◽  
The Matrix ◽  
Detailed Chemical

AbstractCurrent thinking regarding the possible origins and probable evolutionary histories of meteorites is summarized. Selected data concerning the composition, petrology and other characteristics of the CI and CM groups of stony meteorites in which layered minerals principally occur are then presented. Layered compounds, mainly phyllosilicates, are shown to form a major part of the fine-grained matrix of the CI and CM meteorites, which are classified as carbonaceous chondrites. The results of recent investigations of matrix mineralogy are reviewed, with particular emphasis on the findings of electron microscopy. Several forms of Fe-Mg-serpentine have been identified as the principal phyllosilicates. ‘Poorly-characterized phases’ in CM meteorites have proved to be tochilinite and intergrowths of tochilinite with serpentines. The results generally indicate that the phyllosilicates and most other matrix minerals formed by aqueous alteration in the regoliths of the CI and CM parent bodies; but there is isotopic evidence for the incorporation of components and possibly mineral grains which predate the solar nebula. It is concluded that more detailed chemical and mineralogical information about the phyllosilicates and associated minerals will enable useful constraints to be placed on the possible identities of their precursors and the environments in which both they and the matrix minerals formed.

scholarly journals Discovery of fossil asteroidal ice in primitive meteorite Acfer 094

2019 ◽  
Vol 5 (11) ◽  
pp. eaax5078 ◽  
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.

scholarly journals Carbonaceous Chondrites and the Condensation of Elements from the Solar Nebula

2020 ◽  
Vol 897 (1) ◽  
pp. 82
Author(s):  
Hauke Vollstaedt ◽  
Klaus Mezger ◽  
Yann Alibert
Keyword(s):  
Solar Nebula ◽  
Carbonaceous Chondrites

scholarly journals Cosmic Dust Synthesized in Reducing Environments

1980 ◽  
Vol 90 ◽  
pp. 355-356
Author(s):  
B. N. Khare ◽  
Carl Sagan
Keyword(s):  
Organic Molecules ◽  
Solar Nebula ◽  
Thermal Dissociation ◽  
Gas Chromatography Mass Spectrometry ◽  
Carbonaceous Chondrites ◽  
Microwave Line ◽  
Electrical Discharges ◽  
Interstellar Gas ◽  
Dissociation Temperature ◽  
Measured Resistivity

A variety of complex dark brown organic solids called tholins have been produced from a mixture of cosmically abundant gases upon irradiation with ultraviolet light or electrical discharges (Sagan and Khare 1979). Such tholins were probably produced in the primitive solar nebula that contributed to the present composition of carbonaceous chondrites, comets, interstellar grains and gas. Spark tholins produced from approximately equimolar mixtures of CH4 and NH3, with 2.6% H20 exhibit 50% thermal dissociation temperature of about 900°C. Sequential and non-sequential pyrolysis followed by gas chromatography/mass spectrometry are employed to study both UV (Khare et al. 1978) and spark tholins. Typical pyrolyzates of spark tholins include alkanes, alkenes, aromatic hydrocarbon, abundant nitriles, pyrroles, pyrazines and alkylbenzenes. Organic molecules uncovered by microwave line spectroscopy of the interstellar gas are plausibly derived as spallation products of interstellar tholins comparable to the origin we propose for cometary nitriles and aldehydes as the spallation products of the cometary tholins. Spark tholins are highly insulating. Their measured resistivity is 71.4 × 108 ohms-cm and does not change up to a pressure of 105 bars.

scholarly journals Fine-grained volatile components ubiquitous in solar nebula: Corroboration from scoriaceous cosmic spherules

2018 ◽  
Vol 53 (6) ◽  
pp. 1207-1222 ◽  
Author(s):  
N. G. Rudraswami ◽  
D. Fernandes ◽  
A. K. Naik ◽  
M. Shyam Prasad ◽  
S. Taylor
Keyword(s):  
Solar Nebula ◽  
Volatile Components ◽  
Fine Grained ◽  
Cosmic Spherules

scholarly journals 1. High-Temperature Condensates in Carbonaceous Chondrites

1977 ◽  
Vol 39 ◽  
pp. 507-516
Author(s):  
L. Grossman
Keyword(s):  
High Temperature ◽  
Trace Element ◽  
Solar Nebula ◽  
Trace Element Content ◽  
Group Iv ◽  
Carbonaceous Chondrites ◽  
Equilibrium Thermodynamic ◽  
Iron Meteorites ◽  
Solar Composition ◽  
Different Types

Equilibrium thermodynamic calculations of the sequence of condensation of minerals from a cooling gas of solar composition play an important role in explaining the mineralogy and trace element content of different types of inclusions in carbonaceous chondrites. Group IV B iron meteorites and enstatite chondrites may also be direct condensates from the solar nebula. Condensation theory provides a framework within which chemical fractionations between different classes of chondrites may be understood.

Warkite, Ca2Sc6Al6O20, a new mineral in carbonaceous chondrites and a key-stone phase in ultrarefractory inclusions from the solar nebula

2020 ◽  
Vol 277 ◽  
pp. 52-86 ◽  
Author(s):  
Chi Ma ◽  
Alexander N. Krot ◽  
John R. Beckett ◽  
Kazuhide Nagashima ◽  
Oliver Tschauner ◽  
...  
Keyword(s):  
Solar Nebula ◽  
New Mineral ◽  
Carbonaceous Chondrites
Sign in / Sign up

Export Citation Format

Share Document