DISCUSSION ON THE DEFORMATION BAND AND MAGNITUDE OF THE 1515 YONGSHENG EARTHQUAKE IN YUNNAN PROVINCE
Guo Shunmin Xiang Hongfa (Institute of Geology, SSB, Beijing)Zhang Jing Hu Rongqing. Zhang Guowei (Seismological Bureau of Yunnan Province,)
The Yongsheng earthquake took place on the north end of the Chenghai fault zone. The distribution of the seismic deformation band coincides with that of the Chenghai fault zone. The deformation band co'nsists of ground fissures, ground collapses, steep ridges, -landslips, landslides and cliffs of displacement, etc. The deformation band is about 42 km long, 8km wide. The dislocation quantity is from 1 to 2 m. The magnitude (M≥7.5)of the earthquake has been determined. There are many ancient seismic phenomena in the Yongsheng earthquake area, including steep fault ridges, ground fissures, landslide wedges, ground collapses' and landslips, etc. It favours the analysis of the seismic risk to go further into the phenomena.