Geochemical Study on the Oldest Halite Fossil in the Solar System

太阳系最古老的石盐化石的地球化学研究

基本信息

批准号：
13440165
负责人：
NAGAO Keisuke
金额：
$ 9.15万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13440165/
关键词：
noble gas isotopes halite halogens neutron irradiation I-Xe age ^<40>Ar-^<39>Ar age Zag meteorite formation age 希ガス同位体ハロゲン I-Xe年代 Zag隕石希ガス質量分析 Ar-Ar年代 Allende隕石顕微ラマン分光ダイオードレーザー

项目摘要

Halogens and their crystals (halide) have been investigated in Zag and other halogen containing meteorites by detecting halogen-derived noble gas isotopes ^<80>Kr, ^<82>Kr and ^<128>Xe^<129>Xe from extinct nuclide was ^<129>I also measured in these meteorites. Halide crystals are dark phase portion of the Zag meteorite. Size of most crystals are estimated to be smaller than 0.1 mm, which would be surrounded by silicates insoluble in water. Halogens are also concentrated in small materials in Yamato-74191 (L3.6) meteorite. The halogen enrichments in these meteorite are likely resulted by liquid water with high concentrations of halogens presented on their parent planetesimals. Though origin of the waters is not clear, they might have been brought through bombardment by water containing objects such as carbonaceous chondrites or comets.To study the event concerning the halogen enrichments, we constructed noble gas extraction and purification line for noble gas analysis of neutron irradiated meteorites. Modification of VG3600 noble gas mass spectrometer used for ^<40>Ar-^<39>Ar dating was carried out to improve sensitivity and stability of the mass spectrometer in the Radioisotope Center, University of Tokyo. Combining the noble gas line and the mss spectrometer, I-Xe dating of meteorites can be measurable for the first time in Japan. This method began to clarify the timing of halogen enrichment process in meteorites.

通过检测卤素来源的贵族同位素同位素 ^<80> kr， ^<82> kr， ^<82> kr和 ^<128> kr和 ^<128> Xe ^<129> Xe Xe在ZAG和其他含有陨石中，已经在ZAG和其他含有陨石的卤素中研究了卤素及其晶体（卤化物（卤化物）（卤化物）（卤化物（卤化物）），来自Extinction的卤素 ^<80> KR， ^<82> kr和 ^<128> Xe ^<129> Xe），来自Extinc的核酸 ^<80>）卤化物晶体是ZAG陨石的暗相部分。大多数晶体的尺寸估计小于0.1毫米，这将被硅酸盐包围在水中。卤素也集中在大托-74191（L3.6）陨石中的小型材料中。这些陨石中的卤素富集很可能是由液态水产生的，液态水含有高浓度的卤素。尽管水的起源尚不清楚，但它们可能是通过含有碳质软管或彗星的水的轰击来引起的。为了研究有关卤素富集的事件，我们为中子辐射的meteorites构建了质量的气体提取和纯化线，以进行高贵的气化线。对 ^<40> ar- ^<39> AR进行的VG3600贵重气体质谱仪的修饰是为了提高东京大学放射性分析中心的质谱仪的敏感性和稳定性。结合贵族气线和MSS光谱仪，可以在日本首次测量陨石的I-XE年代。该方法开始阐明陨石中卤素富集过程的时机。