Search of intersteller media and the evolution to planetary matters.

星际媒体搜索和行星物质的演化。

• 批准号: 09440186
• 负责人: YURIMOTO Hisayoshi
• 金额: $ 6.91万
• 依托单位: TOKYO INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09440186/
• 关键词: Meteorite; Oxygen; Secondary ion mass spectrometry; interstellar medium; isotope microscope; solar system; isotope; 惑星系; 珪素; マグネシウム; 2次イオン質量分析法

Interstellar media in primitive meteorites are only clue to clarify presolar history. The difference between interstellar media and solar matters is only isotope ratio of elements. We have made in-situ measurements of isotope ratios, textures, shapes and crystal structures for individual fine particles in primitive meteorites. The goal of in this study is construction of new scenario for material evolution from interstellar media to planetary matters.A novel micro-scale analysis for oxygen isotope ratios has been developed by secondary ion mass spectrometry. A calcium-aluminum-rich inclusion (CAI) from the Allende meteorite was analyzed and found to contain melilite crystals with extreme oxygen-isotope compositions (-5 percent oxygen-16 enrichment relative to terrestrial oxygen-16). The oxygen isotopic variation measured among the minerals (melilite, spinel, and fassaite) indicates that crystallization of the CAI started from oxygen-16-rich materials that were probably liquid droplets in the solar nebula, and oxygen isotope exchange with the surrounding oxygen-16-poor nebular gas progressed through the crystallization of the CAI.Additional oxygen isotope exchange also occurred during subsequent reheating events in the solar nebula. The 160-rich dust and 160-poor gas continued together in the solar nebula from the CAI-forming period until the chondrule-forming period.A possible scenario for new evidence would be an active protosun with bipolar out-flow. Interstellar media near the protosun has been processed thermally and then launched into outer solar system. Therefore, composition of solar nebulae distributed heterogeneously along radial direction, The characteristics of composition and isotope ratio of each planet have been achieved in the first million years of solar system evolution.

原始陨石中的星际介质是澄清前太阳历史的唯一线索。星际介质和太阳物质的区别只是元素的同位素比。我们对原始陨石中单个细颗粒的同位素比率、纹理、形状和晶体结构进行了现场测量。本研究的目标是构建从星际介质到行星物质的物质演化的新场景。通过二次离子质谱法开发了一种新颖的氧同位素比微尺度分析方法。对阿连德陨石中的富含钙铝的包裹体 (CAI) 进行了分析，发现其含有具有极端氧同位素组成的黄长石晶体（相对于陆地氧 16 而言，氧 16 富集度为 -5%）。测量的矿物（黄长石、尖晶石和铁赛石）之间的氧同位素变化表明，CAI 的结晶始于富含氧 16 的物质，这些物质可能是太阳星云中的液滴，并且与周围的氧 16 进行氧同位素交换-贫质星云气体通过 CAI 的结晶而进展。在太阳星云随后的再加热事件中也发生了额外的氧同位素交换。从 CAI 形成期到球粒形成期，富含 160 的尘埃和贫乏 160 的气体在太阳星云中持续存在。新证据的一个可能场景是具有双极流出的活跃原太阳。原太阳附近的星际介质经过热处理后发射到太阳系外。因此，太阳星云的成分沿径向呈不均匀分布，各行星的成分和同位素比的特征是在太阳系演化的最初百万年中得到的。

项目成果

Kurosawa, M., Yurimoto, H. and Sueno, S.: "Patterns in the hydrogen and trace element compositions of mantle olivines." Phys.Chem.Min.24. 385-395 (1997)

Kurosawa, M.、Yurimoto, H. 和 Sueno, S.：“地幔橄榄石的氢和微量元素组成的模式。”

Yurimoto,H.,Ito,M.and Nagasawa,H.: "Oxygen isotope exchange between refractory inclusion in Allende and solar nebula gas." Science. 282. 1874-1877 (1998)

Yurimoto, H.、Ito, M. 和 Nagasawa, H.：“阿连德难熔包裹体与太阳星云气体之间的氧同位素交换。”

Yurimoto, H., Matsumoto, K., Kim, K.Kitajima, H., Kosaka, K.and Hirata, H.: "Development of solid-state two-dimensional ion imaging device and new computer control system for SIMS." Secondary Ion Mass Spectrometry SIMS X,Wiley. 987-990 (1997)

Yurimoto, H.、Matsumoto, K.、Kim, K.Kitajima, H.、Kosaka, K. 和 Hirata, H.：“固态二维离子成像装置和 SIMS 新型计算机控制系统的开发。”

Yurimoto, H., Matsumoto, K., Kim, K. Kitajima, H., Kosaka, K. and Hirata, H.: "Development of solid-state two-dimensional ion imaging device and new computer control system for SIMS." Secondary Ion Mass Spectrometry SIMS X. 987-990 (1997)

Yurimoto, H.、Matsumoto, K.、Kim, K. Kitajima, H.、Kosaka, K. 和 Hirata, H.：“固态二维离子成像装置和 SIMS 新型计算机控制系统的开发。”

Taura, H., Yurimoto, H., Kurita, K. and Sueno, S.: "Pressure dependence on partition coefficients for trace elements between olivine and the coexisting melts." Phys. Chem. Mineral.25. 469-484 (1998)

Taura, H.、Yurimoto, H.、Kurita, K. 和 Sueno, S.：“橄榄石与共存熔体之间微量元素分配系数的压力依赖性”。