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Showing 1 to 8 of 8 for “"shock metamorphism"”.
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Investigation of Shocked Basalts from Vargeão Dome and Vista Alegre: Implications for the Search for Life on Mars
… micro-X-ray diffraction (μXRD), the degree of shock metamorphism in plagioclase was quantitively determined. Measuring the full-width-at-half-maximum of diffraction peaks reveals increased strain-related mosaicity. This is correlated with increased optical evidence of deformation. Density and …
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Characterization and chronology of refractory inclusions (CAIs) in the CV3 chondrite NWA 4502
… secondary hydrothermal alteration, thermal and shock metamorphism that affected CAIs in other CV chondrites. Even though NWA 4502 shows pristine parent-body characteristics, complexities discovered in some of the isotope systems especially Rb-Sr indicate significant imprint of terrestrial …
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Characterization and chronology of refractory inclusions (CAIs) in the CV3 chondrite NWA 4502
… secondary hydrothermal alteration, thermal and shock metamorphism that affected CAIs in other CV chondrites. Even though NWA 4502 shows pristine parent-body characteristics, complexities discovered in some of the isotope systems especially Rb-Sr indicate significant imprint of terrestrial …
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Fluids in Planetary Systems
… impactites to determine the effects of shock metamorphism on fluid inclusion properties; and (2) numerical thermodynamic equilibrium modeling of aqueous alteration processes on Mars. Results of impact experiments and analyses of fluid inclusions in rocks from the Ries Crater and Meteor …
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The discovery of baddeleyite (ZrO2) and chrome spinel in the basal Rooiberg Group of the 2.057 Ga Bushveld Complex, South Africa: Implications for the impact and igneous scenarios for the petrogenesis of the Rooiberg Group.
… of one or more bolides. Although evidence for shock metamorphism, key to verifying an impact origin, has not been found, it has been proposed that unique quench textures in the Basal Rhyolite formed during quenching from impact-induced superheat (T > 1686° C). The presence of coexisting zircon …
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Compositional Analysis of the Martian Meteorites Northwest Africa 6342 and Northwest Africa 10961
… and NWA 10961 have experienced high levels of shock metamorphism as demonstrated by substantially fractured minerals, melting and subsequent crystallization of plagioclase into maskelynite, and the fine-grained texture of recrystallized olivine. The recrystallization of plagioclase required an …
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Reassessing the Holleford impact structure: Applying modern techniques to a classic Canadian crater
… reassess microstructures in accessory minerals. Shock microstructures identified as {-111} twins in titanite, a feature which previous studies have hypothesized to be diagnostic of shock deformation at pressures between 12-17 GPa, were observed in one Holleford sample. Shock pressures for drill …
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Raman Spectroscopy and Synchrotron X-ray Diffraction Study of Lunar and Terrestrial Plagioclase Feldspar at High-Pressure and High-Temperature Conditions
… information about impact cratering process. Shock features in plagioclase from Mistastin Lake impact structure, Canada, and Apollo samples returned from the Moon were investigated. A series of progressive optical shock features were observed, and their Raman spectra was collected …