On the basis of geochemical and geophysical data, the present mantle possesses three-dimensional chemical heterogeneity. It is suggested that the evolution of geochemical heterogeneity (GCH) should be divided into thr...On the basis of geochemical and geophysical data, the present mantle possesses three-dimensional chemical heterogeneity. It is suggested that the evolution of geochemical heterogeneity (GCH) should be divided into three stages. The first stage is EGCH (～1.8Ga), the second stage can be regarded as the homogenizing or transform stage around 1.8Ga, and the third stage is later geochemical heterogeneity (LGCH). This note roughly summarizes EGCH of global lead isotopes composition, and suggests that the origin of EGCH stemmed from the primary/initial chemical heterogeneity (PCH) of planetesimals accumulating on the earth.展开更多
文摘On the basis of geochemical and geophysical data, the present mantle possesses three-dimensional chemical heterogeneity. It is suggested that the evolution of geochemical heterogeneity (GCH) should be divided into three stages. The first stage is EGCH (～1.8Ga), the second stage can be regarded as the homogenizing or transform stage around 1.8Ga, and the third stage is later geochemical heterogeneity (LGCH). This note roughly summarizes EGCH of global lead isotopes composition, and suggests that the origin of EGCH stemmed from the primary/initial chemical heterogeneity (PCH) of planetesimals accumulating on the earth.
