From the Point of view of the focal mechanizm and behaviour of ground crack, the component of right-lateral shear strike slip was dominant and at the same time with dip slip during Tangshan earthquake.

• 震源机制结果与极震区地裂缝的力学性质,都说明唐山地震是以右旋剪切走向滑动为主且兼倾向滑动的主震型大地震。