基于变形分解与斜向汇聚理论的秦岭—大别造山带构造变形研究

Some thoughts on strain research on the Qinling-Dabie orogenic belt

板块汇聚碰撞过程中,常常造成应力矢量与板块边缘的非直交关系,导致平移分量和缩短分量的产生,它们并非不同时期、不同应力场的产物;这种斜向汇聚产生大陆造山带的不对称扇型结构及花状构造,也可能是大陆增生保存的重要形式之一;变形分解作用使得岩石在变形过程中产生纯剪变形分量和单剪变形分量,且不受尺度控制;该理论常被应用于解释造山带尺度的许多构造问题,在秦岭造山带中进行变形分解和板块斜向汇聚研究,有望在理论上有所突破。

The stress direction is usually oblique to the plate margin in the process of plate convergence and collision,resulting in strike-slip component and shortening component which are of the same age and in the same stress field. The oblique convergence makes the continental orogenic belt with the flower structure. This is an important type of the continental growth. In the process of rock deformation,strain partitioning brings about the simple shear component and the pure shear component which have no relation to size. The theory of the strain partitioning can explain a lot of structural questions of orogenic belts. Carrying out the study of strain partitioning and oblique convergence in the Qinling orogenic belt may give rise to a theoretic breakthrough.