Nebular Fractionation, Classification and Formation Locationof Chrondritic Meteorites

这个项目的目的是通过研究球粒陨石来更多地了解太阳星云的历史。该计划将分析球粒陨石，以获得与以下相关的成分数据：1)导致球粒陨石形成的星云过程，以及2)不同球粒陨石群形成的日心距离。大约30种元素将通过高精度的中子活化分析来确定。目前的主要焦点是对不寻常的普通球粒陨石的研究，特别是那些成分介于主要(H，L，LL)组成员之间的球粒陨石。将使用物相分析来确定更多这类物质的位置，并将与其他集团合作，利用大量元素数据和惰性气体同位素数据来评估这些物质是否与主要集团起源于同一母体。将分析稀有类型的球粒陨石，并根据星云分馏过程解释残留球粒陨石中的分馏趋势。

The purpose of this project is to learn more of the history of the solar nebula by studying chondritic meteorites. The plan is to analyze chondrites to obtain compositional data that relate to: 1) the nebular processes that led to the formation of the chondrites, and 2) the heliocentric distances at which the different chondrite groups formed. Approximately 30 elements will be determined by high precision neutron activation analysis. The main current focus is on the study of unusual ordinary chondrites, particularly those that have compositions intermediate between those of members of the main (H, L, LL) groups. Phase analysis will be used to locate more of these and, in collaboration with other groups, bulk elememntal data and noble-gas isotopic data will be used to assess whether these originated in the same parent bodies as the main groups. Rare classes of chondrites will be analyzed, and fractionation trends among relted chondrites interpreted in terms of nebular fractionation processes.