Evaporation metamorphism in the early solar nebula. Evaporation experiments on the melt FeO-MgO-SiO2-CaO-Al2O3 and chemical fractionations of primitive materials.

Hashimoto, Akihiko

doi:10.2343/geochemj.17.111

Cited by 161 publications

(139 citation statements)

References 51 publications

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“…Removal of volatiles by evaporation from chondrules and melt droplets has been proposed by Larimer and Anders ( 1967), Wolf and Anders ( 1980), and W&&e et al ( 1981, 1984). Experimental investigations of the chemical changes taking place during evaporation of Murchison and Allende chondrites by Notsu et al ( 1978), Hashimoto et al ( 1979), and Hashimoto (1983) have shown that evaporation can produce chemical fractionations similar to those produced by condensation.…”

Section: Evaporation Of Chondritic Materialsmentioning

confidence: 99%

“…With the exception of the Cl chondrites, all primitive meteorites have large numbers of chondrules, which indicate brief localized melting events (T = 1700-2000 K), during which volatile element depletion could have taken place (Larimer and Anders, 1967;Ganapathy and Anders, 1974). Hashimoto et al ( 1979) and Hashimoto ( 1983) proposed that thermal metamorphism of dust in the solar nebula, resulting in evaporation of the more volatile elements, could produce chemical fractionations identical in most respects to those produced by condensation from a cooling gas. Thus, a cold nebular model with an initial dust content inherited from the interstellar medium, accompanied by rapid localized heating events, could produce all the observed volatile depletions while preserving the oxygen isotopic anomalies, isotopic anomalies in other elements, and presolar grains (Sic, graphite, diamonds, etc.).…”

Section: Thermal History Of Matter and Oxygen Isotopesmentioning

confidence: 99%

“…There have been many proposed means of accomplishing this, including loss from heated grains (Hashimoto et al, 1979;Hashimoto, 1983), loss from molten chondrules (Larimer and Anders, 1967;Ganapathy and Anders, 1974;Wolf and Anders, 1980), and loss from impact-disrupted planetesimals (Zook, 198 1;Wgnke et al, 198 1, 1984;cf. Anders, 1964, for earlier versions), which is sometimes taken to be identical to chondrule formation (Zook, 1981).…”

Section: Nebular Processing-chondrules and Dust Grainsmentioning

confidence: 99%

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Potassium isotope cosmochemistry: Genetic implications of volatile element depletion

Humayun

Clayton

1995

Geochimica et Cosmochimica Acta

308

185

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Section: Evaporation Of Chondritic Materialsmentioning

confidence: 99%

Section: Thermal History Of Matter and Oxygen Isotopesmentioning

confidence: 99%

Section: Nebular Processing-chondrules and Dust Grainsmentioning

confidence: 99%

See 1 more Smart Citation

Potassium isotope cosmochemistry: Genetic implications of volatile element depletion

Humayun

Clayton

1995

Geochimica et Cosmochimica Acta

308

185

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“…Al-rich chondrules tend to be finer-grained than coarse-grained inclusions from carbonaceous chondrites. Since Na 2 O is quite volatile in silicate melts [13,47,48], the frequent presence of glass and skeletal fassaite [44] together with Na20 contents usually in excess of 1 wt.% [44,45], suggests that cooling rates were faster for Al-rich chondrules than for Allende coarse-grained inclusions [49].…”

Section: Relationships Of Type C's To Other Caismentioning

confidence: 99%

“…Wark [3] presented two substantive arguments against the possibility that type C inclusions were extensively volatilized during the melting event. First, bulk compositions of type C's have Si/Mg ratios that are much higher than those expected upon volatilization of chondritic material [13]. A precursor with an Si/Mg ratio higher than the chondritic value could be proposed, but chondrules, bulk chondrites and the most likely silicarich interstellar grains (e.g., olivine, enstatite) all have lower Si/Mg than do type C's [14].…”

Section: Effect Of Secondary Alteration Productsmentioning

confidence: 99%

The origin of type C inclusions from carbonaceous chondrites

Beckett

Grossman

1988

Earth and Planetary Science Letters

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Type C inclusions are plagioclase-rich, Ca-, Al-rich inclusions found in carbonaceous chondrites. They formed as solid condensates which were later melted in an event that destroyed the original condensate grains. Neither the melting event nor secondary alteration had a significant effect on bulk composition. Two stages in the condensation history can be discerned on the basis of major element bulk compositions. As in type A inclusions, the condensate phase assemblage originally consisted of melilite + spinel + perovskite + hibonite. Type C's were, however, significantly enriched in spinel relative to unaltered portions of most type A's. In contrast to type A's, condensate grains of spinel and melilite in type C's reacted partially with a coexisting gas to produce anorthite + diopside. One-half to two-thirds of the silica now in type C inclusions was introduced by this process. The reactions involving melilite and spinel that are predicted by equilibrium condensation calculations for a cooling gas of solar composition did not occur, probably due to kinetic constraints. Type C's may be related to Al-rich chondrules in ordinary chondrites by the addition of olivine and albite. Bulk compositions of Al-rich chondrules in enstatite chondrites are consistent with the addition of orthopyroxene and albite to type C inclusions. Thus, types A and C inclusions and Al-rich chondrules could represent sequences of condensates removed from interaction with the primitive solar nebula at progressively lower temperatures. If Al-rich chondrules represent the high-temperature component in chondritic material, then type C inclusions rather than the more common subgroups of CAIs could be the true parents of chondrites.

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Micrometeorite flux on Earth during the last ~50,000 years

2013

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[1] Flux of micrometeorites is estimated by using cosmic spherule counts from a seafloor area of 2.50 m 2 from the Indian Ocean. The spherules are recovered from sediment samples in close-spaced locations from the Indian Ocean after sieving 293 kg of sediment. The terrestrial age of the spherules has a range of 0-~50,000 years. The spherules have a size range of 57-750 μm (average size 265 ± 92 μm). The diameter of the spherules increases from scoriaceous-barred-cryptocrystalline-glassy types. The time-averaged flux of the spherules is 160 t/yr, a sizeable mass (>60%) resides in the >300 μm fraction; the slope of distribution is similar to that of Deep-Sea Spherules but significantly different from other collections which have lower average diameters. It is observed here, a significant population of cosmic dust resides in the larger sizes which can be recovered by sampling large areas in time and space. The spherule textures are similar to that of unbiased collections from the polar regions, indicating that the textural types of cosmic dust that have been raining on the Earth during the last 50 kyr have been constant regardless of size. Major element chemistry of a majority of the spherules show elemental ratios that are close to a CM or CI chondritic parent body; a single spherule (0.2% of the population) suggests an achondritic parent body. Unbiased collections spanning large areas temporally and spatially enlarge the inventory of the Earth-crossing meteoroid complex and provide valuable inputs for models on cosmic dust accretion.

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Evaporation metamorphism in the early solar nebula. Evaporation experiments on the melt FeO-MgO-SiO2-CaO-Al2O3 and chemical fractionations of primitive materials.

Cited by 161 publications

References 51 publications

Potassium isotope cosmochemistry: Genetic implications of volatile element depletion

Potassium isotope cosmochemistry: Genetic implications of volatile element depletion

The origin of type C inclusions from carbonaceous chondrites

Micrometeorite flux on Earth during the last ~50,000 years

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