摘要
地球是太阳系的一部分 ,研究地球的成因和演化必须要与太阳系的形成结合起来。文章在综合最新的地球化学、地球物理和天体化学研究资料的基础上 ,对地球的不均一成因进行了理论上的推导。对星子学说、地球的多阶段堆积模型和地球化学不均一性以及它们的相互关系进行了论述 ,从行星演化的角度阐述地球不均一成因的理论框架。根据行星起源的星子学说 ,以及天体化学、地球化学和深部地质地球化学和地球物理资料的多重限制 ,行星地球的增生经历了两个主要阶段 ,即原地球的形成阶段和晚期星子堆积形成上地幔镶饰层阶段。早前寒武纪岩石的铅、钕、氧同位素的研究表明 ,在地球形成的初期就存在化学不均一性 。
The Earth is a part of the solar system, the study on the origin and the evolution of the Earth should connect with the formation of the solar system. Based on recent data of geochemistry, geophysics and cosmochemistry, the authors introduce the hypotheses about the origin and the evolution of the Earth's heterogeneity, including the planetesimal theory and the accumulation model of the Earth,geochemical heterogeneity and their relationships. According to the planetesimal theory of the origin of planet and the data of cosmochemistry, geochemistry and geology geochemistry, and geophysics of the Earth's interior; the process of accumulation of planetary Earth can be divided into two stages:in the early stage, the primordial Earth was formed; and in the late stage, the planetesimal accumulated on the primordial Earth and the decorated layer of upper mantle was formed. The study of lead, neodymium and oxgen isotopic compositions of Precambrian rocks indicated that the heterogeneity has already existed in the early stage of the earth formation, and that the differences of isotopic composition in different crust terranes demand the difference of chemical composition resulted from planetesimals accumulation.
出处
《地学前缘》
EI
CAS
CSCD
2002年第3期23-30,共8页
Earth Science Frontiers
基金
中国科学院知识创新工程项目 (KZCX2 -115 )
中国科学院院长基金特别资助项目
中国科学院地球化学研究所所长择优选择基金资助项目
