Study on the initial states of the solar system by measuring microdistribution of noble gases in meteorites

为了确定影响太阳系早期物质演化的物理化学过程和条件，用激光显微探头技术测量了稀有气体的微观分布，并与陨石结构进行了比较。碳质球粒陨石中的捕获气体主要存在于球粒陨石边缘。在破碎部分发现了太阳气体，但在原始吸积岩中没有发现太阳气体，这表明太阳星云的物质密度太高，以至于太阳风没有到达球粒状边缘的形成区域。阿连德的气体损失是通过人为施加30到70 Gpa的冲击冲击来确定的。在70 GPA冲击下，部分岩石熔化，Q-Gas损失70%，而被困在太阳前钻石中的HL-Gas则保持不变。还研究了层状硅酸盐矿物脱水后的气体损失，以寻找早期太阳星云的物理化学条件。脱水碳质球粒陨石中的气体浓度受加热温度和时间以及有机碳的石墨化作用的制约，对宇宙尘IDP、南极微陨石和深海磁性球粒进行了稀有气体、微量元素和矿物组成的分析。利用同步辐射的高光度，测定了IdP和微陨石的矿物组成和磁球的微量元素丰度。

In order to determine physico-chemical process and condition to affect the evolution of materials in the early solar system, noble-gas microdistribution was measured by a laser microprobe technique and was compared to the meteorite texture. Trapped gases in carbonaceous chondrites reside mainly in chondrule rims. Solar gas was found in comminuted parts but not in primary accreted rocks, indicating that the material density of the solar nebula was so high that the solar wind did not reach the formation region of chondrule rims. Gas-loss from Allende was determined by artificially applying impact-shocks of 30 to 70 GPa to it. At 70 GPa shock, part of rock melted and 70% of Q-Gas was lost, whereas HL-gas that was trapped in presolar diamond was retained without loss. Gas-loss-following dehydration of phyllosilicate minerals was studied as well to find physico-chemical conditions in the early solar nebula. Gas concentration in dehydrated carbonaceous chondrites is constrained by heating temperature and time as well as graphitization of organic carbon.Cosmic dusts including IDP, Antarctic micrometeorites and magnetic deep-sea spherules were analyzed for noble-gas, trace element and mineral composition. Determinations of mineral compositions of IDP and micrometeorites and trace element abundance for magnetic spherules were carried out using high luminosity of synchrotron radiation.