کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5783468 1637956 2017 82 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Calcium-aluminum-rich inclusions recycled during formation of porphyritic chondrules from CH carbonaceous chondrites
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات ژئوشیمی و پترولوژی
پیش نمایش صفحه اول مقاله
Calcium-aluminum-rich inclusions recycled during formation of porphyritic chondrules from CH carbonaceous chondrites
چکیده انگلیسی
We conclude that CH porphyritic chondrules formed by incomplete melting of isotopically diverse solid precursors, including mineralogically and isotopically unique CAIs commonly observed only in CH chondrites. Therefore, the CH porphyritic chondrules must have formed in a distinct disk region, where the CH CAIs were present at the time of chondrule formation. Because most CH CAIs avoided chondrule melting, we infer that chondrule formation was highly localized. These observations preclude formation of CH porphyritic chondrules by splashing of molten planetesimals, by impact processing of differentiated planetesimals, and by large scale nebular shocks, e.g., shocks driven by disk gravitational instabilities or by X-ray flares. Instead, they are consistent with small-scale chondrule-forming mechanisms proposed in the literature, such as nebular processing of dust balls by bow shocks and by current sheets.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geochimica et Cosmochimica Acta - Volume 201, 15 March 2017, Pages 185-223
نویسندگان
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