Isotope anomalies in meteoritic materials and the dynamical evolution of the solar nebula: Constraints from Cr, Ti and O isotopes

陨石及其组分同位素组成的变化对理解太阳星云的化学和同位素演化以及原行星盘中原始尘埃的运输和混合动力学起着关键作用。在本研究中，我们将研究原始球粒陨石组分中Cr和Ti同位素的变化，特别关注球粒和基质。我们将研究这些球粒陨石成分在多大程度上是同位素不均匀的，以及这些成分在不同的球粒陨石群中是否具有同位素差异。本研究的第二个主要重点将是对反映星云尘埃中不同核合成成分（例如54Cr球粒和基质）的不均匀分布与反映星云气体的同位素演化及其与固体相（O同位素）相互作用的同位素异常进行系统和综合研究。这项研究的主要成果之一将是为整个原行星盘的同位素变异性及其对太阳系内行星储层的整体化学和同位素演化的影响提供新的和坚定的约束。这些数据将为早期太阳星云的动态演化提供关键信息。

Variations in the isotopic composition of meteorites and their components play a pivotal role in understanding the chemical and isotopic evolution of the solar nebula and the dynamics of transport and mixing of primordial dust within the protoplanetary disk. In this study, we will investigate Cr and Ti isotope variations in components of primitive chondrites with a particular focus on chondrules and matrix. We will investigate the extent to which these chondrite components are isotopically heterogeneous and as to whether these components are isotopically distinct among the different chondrite groups. A second major focus of this study will be the systematic and combined investigation of isotope anomalies that reflect a heterogeneous distribution of distinct nucleosynthetic components in the nebula dust (e.g., 54Cr chondrules and matrix) with those that reflect the isotopic evolution of the nebula gas and its interaction with solid phases (O isotopes). One of the major outcomes of this study will be to provide new and firm constraints on the isotope variability throughout the protoplanetary disk and its imprint on the bulk chemical and isotopic evolution of planetary reservoirs within the inner solar system. These data will provide critical information regarding the dynamical evolution of the early solar nebula.