STUDY OF MYLONITE AND DEFORMATION OF DUCTILE SHEAR ZONE, DINGJIE AREA

Since the Dingjie Area lies in the middle of Himalayan Orogen Belt in the south of Qinghai Tibet Plateau, it is the key place to study the development and uplifting of Himalaya. In the area, there form many kinds of ductile shear zones defined by their orientation, scale and stage. Within the deformed rocks in these ductile shear zones, there develop so abundant deformational textures such as larsen lineation,rotational porphyroclast,S C fabrics, domino structure, and so on, which shows the deformation of rocks in shear zones mainly resulted from the ductile deformation mechanism. And the deformed rocks are granite mylonites, feldspar quartz mylonites and super mylonite which were formed in the ductile shear zone. Temperature for deformation of ductile shear zone ranges from 208℃ to 559℃.