Abstract: Field geological investigatins and the results of ⁴⁰Ar/³⁹Ar isotopic dating demonstrate that the NNE trending ductile shear zone of the basment of the central sgement of the Yihe Shuhe fault developed during the Jinning Movement period (941Ma). In the process of the continent continent collision during this time,the collisional strike slip tectonics occurred because of the inconsistent collisional boundaries which represents the early activity of the Yihe Shuhe fault. On this basis we have studied the relationship between the basement ductile shear zone,the Yihe Shuhe fault and the Tanlu active fault.

Key words: Active fault, Crustal deformation, Tangcheng Lujang fault zone

摘要： 野外地质现象及⁴⁰Ar/³⁹Ar同位素年龄测定结果证明,沂沭断裂中段的北北东向基底韧性剪切带形成于晋宁期(941Ma)。晋宁期华北、扬子两板块陆-陆碰撞作用过程中,由于碰撞边界不吻合而导致的碰撞走滑构造,代表沂沭断裂的早期活动。在此基础上,探讨了沂沭基底韧性剪切带与沂沭断裂以及郯庐断裂活动的关系。

关键词: 活断层, 地壳形变, 郯庐断裂带