On 12 May, 2008, an earthquake occurred in Longmen Mountains, whose main epicenter is located in Wenchuan of Sichuan. This unexpected hazard is characterized by the huge magnitude, wide affected areas, and the linear distribution of the epicenters. Based on the tectonic geological investigation after the earthquake occurred, the faulting activities triggering the huge earthquake consist of two ... [Show full abstract] episodic stages. Oblique-thrusting and reverse-thrusting are the two kinematic features, which are composed of the two components of strike-slip and thrusting. Between them, the strike-slipping occurred first followed by the reverse thrusting, and then the reverse thrusting dominates mostly. Analyzing the multi-stage slickensides on the fault surfaces, there are three episodes of faulting activities. The first episode is characterized by the oblique-thrusting, the second episode is reverse-thrusting, and the third one is the strike-slipping. The direction of σ1 which triggered the earthquake is NW-SE.