关键词: 云南, 澜沧地震, 断裂, 地震形变带, 地裂缝

Abstract: The seismic deformation zone of M 7.6 Lancang earthquake in 1988 is mainly composed of a series of surface ruptures and distributed along the Muga and Datangzi faults, The mechanical property of right-lateral shear of the deformation zone is analysed. But some segments of the zone exhibit their left-lateral shearing movement.Based on the field investigation and comprehensive analysis of data, it is considered that the axis of principal stress for the event is in NS-NNE direction. The seismic faulting of the event should represent a right-lateral displacement. The ground cracks which exhibit left-lateral displacement were formed by right-lateral displacement of faults.

Key words: Yunnan, Lanchang earthquake, Fault, Deformation zone, Groud fisssure