Mathematics – Logic
Scientific paper
Feb 1987
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1987e%26psl..81..358t&link_type=abstract
Earth and Planetary Science Letters (ISSN 0012-821X), vol. 81, no. 4, Feb. 1987, p. 358-370. MOE-supported research.
Mathematics
Logic
70
Meteoritic Composition, Mineralogy, Silicates, Ureilites, Antarctic Regions, Calcium, Iron, Manganese Oxides, Olivine, Photomicrography, Pyroxenes, Meteorites, Antarctic Meteorites, Ureilites, Stony Meteorites, Mineralogy, Origin, Evolution, Hypotheses, Crystallography, Electron Probe, Silicates, Yamato Meteorites, Yamato 74123, Yamato 74130, Yamato 74659, Composition, Alh 82106, Yamato 790981, Alha77257, Alha78019, Chemistry, Experiments, Differentiation, Texture, Mineralogy, Formation, Temperature, Reduct
Scientific paper
Mineralogical and crystallographic data and electron microprobe analyses of silicate minerals for Antarctic ureilites Y74123, Y74130, Y74659, Y790981, ALHA77257, ALHA78019, and ALH82106 extend the chemical and textural variations among ureilites beyond those known for non-Antarctic urelites. Low-Ca pyroxenes, possibly orthopyroxene, poikilitically enclosed in olivine and coexisting with Mg-rich pigeonites, have been identified in Y74659 and ALHA77257. Coexisting low-Ca pyroxene, pigeonite, and augite, together with the very Fe-rich olivine in ureilites were observed in Y74130. Almost Fe-free pigeonite and diopside coexist in ALH82106. No systematic differentiation trend has been reconstructed from these data, but the pyroxene pairs yield formation temperatures above 1200 C. A weak anticorrelation between MnO and FeO delineated by these pyroxenes suggests that a reduction reaction is responsible for the chemical variations. A working hypothesis for ureilite formation involves high-temperature episodes and a planetisimal-scale collision, which might have facilitated compaction and recrystallization of mafic silicates. During the episodes, Fe-Ni-S eutectic melt and a partial melt rich in Ca, Al, and Fe might have been lost from a carbonaceous-chondrite-like source material.
No associations
LandOfFree
Mineralogy of Antarctic ureilites and a working hypothesis for their origin and evolution does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Mineralogy of Antarctic ureilites and a working hypothesis for their origin and evolution, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mineralogy of Antarctic ureilites and a working hypothesis for their origin and evolution will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1012101