地球深部壳-幔边界的层束精细结构与物理属性研究

Research on Layer-Bundle Fine Structures and Physical Attributes of Crust-Mantle Boundary in Deep Earth

地球深部壳幔边界的介质结构和属性在地球内部圈层结构,特别是岩石圈结构与深层动力过程的研究中占有重要地位。这不仅由于它是地壳与上地幔的分界,而且它与深部物质的分异、调整及其深、浅物质的运移和耦合密切相关。研究结果表明:①通过地震宽角反射和近垂直反射波场效应可分辨其精细结构;②壳幔边界具有高低速相间的薄层、层束状多态结构;③来自壳幔边界复杂结构的地震反射波和宽角反射波具有明显的和各异的波场特征,并具有明显的动力学响应;④壳幔边界是一个主体由榴辉岩组构的化学界面;⑤给出了壳幔边界的广义模式。

The media structures and attributes tant role in the studies on sphere structure in the of crust-mantle boundary in deep earth play an impor- inner earth, especially in the lithosphere and deep dynamic processes. As the boundary between crust and upper mantle, it is closely related with the separation and regulation of deep matter and the movement and coupling of shallow and deep substance. The wavefield characteristics of wide angle and near vertical seismic reflections can be used to study the fine structure of crust-mantle boundary, which has multi-states structure with the thin layers of high velocity alternating low velocity and layer bundles. Near vertical and wide angle seismic reflections from the boundary have obvious and quite different dynamic features. The crust-mantle boundary is a chemical interface composed of mainly with eclogite. A generalize model about the boundary is given in the last.