Abstract:
Zhaoyuan-Pingdu fracture zone in Jiaodong district is one of the most important ore control fracture belts, belonging to Tan-Lu fracture system. Its formation experienced a long evolutional history. Priority to Fenzishan stage, Zhaoyuan-Pingdu fracture zone showed a ductile deformation, with the upgrowth mylonitized belt formed and uplift of Jiaodong geoblack followed. In Yenshan stage, Zhaoyuan-Pingdu fracture zone rejuvenated under the effect of the Mesozoic stress field, and brittle deformation took place as a principal event, thus brittle and ductile deformations were superimposited in the same space.From south to north, the morphotropism ranged from ductile into brittle deformation, companied with the intensive thermal event. At least three times the relative movement took place in Zhaoyuan-Pingdu fracture zone, and the directions changed as follows: left lateral slip, right lateral slip, and then left lateral slip, and the mechanical properties: torsion, torsion tension torsion, and compresso shear. The 40 ?Ar/ 39 Ar isotope dating of muscovite from tectonic schist is(134.26±0.34)Ma, and the isochron of 40 ?Ar/ 36 Ar 39 Ar / 36 Ar (134.50±1.46)Ma.