THE FORMATION AGES OF THE DUCTILE DEFORMATION BELTS IN THE BASEMENT OF THE CENTRAL TANLU FAULT ZONE IN CENTRAL SHANDONG

The ductile deformation belts in the basement of the central Tanlu fault zone in central Shandong can be divided into two types: （1） NE trending ductile deformation belts, which were formed before the emplacement of the Early and Middle Proterozoic granitic intrusives （2 488 Ma） and are characterized by the development of the middle and deep level tectonic gneisses; and （2） NNE trending ductile deformation belts, which were formed in the Jinningian movement （941 Ma） accompanied by the development of middle and shallow level mylonites. A preliminary discussion is made on the formation mechanism and ages of the above mentioned two types of ductile deformation belts.