Eucrite‐type achondrites: Petrology and oxygen isotope compositions <sup>†</sup>
نویسندگان
چکیده
We report petrologic studies and oxygen isotope analyses of normal anomalous eucrites, termed eucrite-type achondrites. Petrologically achondrites can have compositions, vice versa. Two basaltic eucrites with compositions contain pyroxenes Fe/Mn engendered by parent body processes acting on eucrites: solid-state reduction S gas in EET 87542, during crystallization magmatic QUE 94484. Cataclastic breccias PCA 82502 91007 are paired (petrology, oxygen). Although isotopically like Pasamonte, they petrologically distinct. confirm the petrological isotopic anomalies cumulate gabbro 92023; likely formed impact melting mixed materials. Many main group include plagioclases that retain near-liquidus despite metamorphic overprinting. Stannern more sodic plagioclase, which is consistent melt hybridization hypothesis for magma formation. The lack calcic plagioclase suggests reactive exchange anorthite component primary albitic crust. Asteroids modestly different composition produce virtually indistinguishable basalts, providing a ready explanation achondrite suite. Small stochastic variations evolution cause substantial differences rocks produced an asteroid.
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ژورنال
عنوان ژورنال: Meteoritics & Planetary Science
سال: 2021
ISSN: ['1945-5100', '1086-9379']
DOI: https://doi.org/10.1111/maps.13730