扬子克拉通壳、幔结构与深层动力过程

Yangtze craton is very complicated under the multiple tectonic movements. It is the most crucial part in the formation and evolution of South China. In the coupling of the Qinling orgenic belt and Yangtze Craton, of which the migration path is to the north, and spcially in the exchange of deep material and energy and its deep process, they occupy an important position in the research of tectonic system of China, which presents an east-west tectonic belt and south-north structural domain. Constrained by the deep geodynamic process, the Yangtze craton suffer the collision and extrusion by the surrounding blocks, these affect the formation of intracontinent collision orogen and the dfferent types of mountain-basin system. Therefore, a long section of nearly 1200km should be laid, which begins form Xianyang in the north, passes Wanyuan, Zhengan, Kaiyang, Tiandong to the south, and stops on the China-Vietnam border. Along this long section, the high precision observation of natural earthquake should be implemented to get the 3D fine velocity structure of the crust and mantle after the inversion. We want to get the electrical, the density and the magnetic structure from related data collection and some additional observations about the MT sounding, the gravity and magnetic field of the 1200km long section. Also, the deep and shallow structure, the differentiation and interconnection, the response of geophysical boundary filed and deep dynamical process will get a further study.

扬子克拉通是华南大陆形成与演化的重要组成部分，在多期次构造运动作用下构造十分复杂。它在我国东西向构造带和南北向构造地域的整体构造体系中占有重要地位，在研究和探索扬子克拉通向北的运移轨迹和与秦岭造山带的耦合响应，特别是其深部物质与能量的交换及其深层过程研究与探索中乃核心所在。这是由于扬子克拉通受到周边不同块体的碰撞、挤压及其之后的陆内变形和深层动力过程的制约，且影响着陆内造山带的形成和不同类型的盆山系统生长。为此在北起咸阳，向南经万源、正安、开阳、田东直抵中越边境的凭祥布设一条长近1200Km的大剖面，主体进行高精度的天然地震波场观测和数据采集，以反演求取沿剖面辖区的精细的壳、幔三维速度结构，收集已有大地电磁测深数据和重力场、磁力场资料及部分补充测量，给出其电性结构，密度结构和磁性结构特征。进而研究与探索其深、浅结构耦合与分区；地球物理边界场响应及深层动力过程。

四川盆地、百色盆地是华南大陆形成与演化的重要组成部分，在多期次构造运动作用下构造十分复杂。它在我国东西向构造带和南北向构造地域体系中具有重要地位，在研究和探索扬子克拉通向北的运移轨迹和与秦岭造山带的耦合响应，特别是其深部物质与能量的交换及其深层过程研究与探索的核心所在。这是由于扬子克拉通受到周边不同块体的碰撞、挤压及其之后的陆内变形和深层动力过程的制约，且为陆内造山带的形成和不同类型的盆山系统所致。为此，在北起镇巴地区，向南经万源、正安、开阳、田东直抵中越边境的凭祥布设一条长近1200km的大剖面，利用高精度的地球物理数据（包括重力场、磁力场、电磁场、天然地震波场）与高分辨率数据采集，反演刻画了沿剖面辖区的物质属性和精细的壳、幔结构，这一系列新成果对研究与探索其深、浅结构分区和块体界带，盆山耦合的深层过程和大陆动力学响应，是十分重要的。