CARBON IN GLASS INCLUSIONS IN THE ALLENDE METEORITE
CARBON IN GLASS INCLUSIONS IN THE ALLENDE METEORITE
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DOI：
10.1111/j.1945-5100.1989.tb00941.x
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发表时间：
1989-03-01
期刊：
影响因子：
--
通讯作者：
VERHEUL, H
中科院分区：
文献类型：
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作者：
MAKJANIC, J;TOURET, JLR;VERHEUL, H
阿连德CV3碳质球粒陨石球粒中的橄榄石含有两种类型的微米级硅酸盐熔体包裹体：透明玻璃（I型）和失透玻璃（II型）。许多I型包裹体含有大小不等的气泡。II型夹杂物可以是透明的（IIa），有或没有气泡，和棕色（IIb型），有气泡。用拉曼微探针测量了许多夹杂物，以检测可能存在的碳。仅在II型夹杂物中检测到石墨形式的碳。用电子探针和质子探针测定了11个包裹体的成分，以寻找碳对失透包裹体的偏好的可能解释。所测包裹体均富含Si、Al和Ca。这两种类型的包裹体的成分之间没有显着的差异被发现。数据表明，形成的包裹体从熔体中捕获在不断增长的橄榄石晶体，本身结晶从富硅，含气体的熔体。石墨的出现与原始熔体中的气体丰度（如气泡大小所示）之间没有相关关系。因此，碳没有结合成气态物质（例如，CO）。它必须优先溶解在熔体的某些区域。
Olivines in chondrules of the Allende CV3 carbonaceous chondrite contain two types of micron sized silicate melt inclusions: clear glass (type I) and devitrified glass (type II) inclusions. Many of the type I inclusions contain a gas bubble of variable size. Type II inclusions can be transparent (IIa), with or without a gas bubble, and brown (type IIb), with a gas bubble. A number of inclusions were measured with the Raman microprobe to detect possible presence of carbon. Carbon in the form of graphite was detected only in type II inclusions. Compositions of 11 inclusions were determined with the electron microprobe and proton microprobe in search for possible explanation of this preference of carbon for devitrified inclusions. All of the measured inclusions are rich in Si, Al and Ca. No significant differences between the compositions of the two types of inclusions were found. The data suggest that the inclusions formed from the melt trapped in growing olivine crystals, which themselves crystallized from a silicon rich, gas bearing melt. There is no coherent relation between the occurrence of graphite and the gas abundance in the original melt, as indicated by the sizes of gas bubbles. Therefore, carbon was not combined in a gaseous species (e.g., CO). It must have been preferentially dissolved in some domains of the melt.