ABSTRACT
This chapter attempts to illustrate the mechanism of the plane-torsion rockslide. The failure mode and criterion of stability of the rockslide is presented using the example of the Jinpen rockslide, in Heihe River of Xi’an, China, which exhibits a remarkable counterclockwise rotation. The Jinpen rockslide is located on the right side of the valley of Heihe River. The lateral failure surface on the north flank of rockslide, is marked by well-developed fissures on the ground, and at depth is joined to the plane of a preexisting normal fault dipping steeply towards the south. The rockslide mass is markedly separated from the parent mass along its both northern boundary and underlying slip surface, and yet, on the southern end it has not detached from the parent mass, i.e. in contrast to the well-developed north flank the south flank is under development.
