“S”-SHAPED SHEAR FOLDS AND ORGANIZATION OF DUCTILE SHEAR ZONES IN THE EASTERN SECTOR OF THE SOUTHERN MARGIN OF THE YANGTZE BLOCK

In the low-grade metamorphic rock series of the Middle Proterozoic Zhujia Group in theeastern sector of the southern margin of the Yangtze biock, there are developed a series of“s”-shaped shear folds,accompanied by the organization of en-echelon,reticular and parallelshear zones. Their formation and evolution process indicate that the collision of the Caledo-nian Yangtze block and Nanhua block resulted in their dextral strike-slip and assembling.