Surface rupture zone of the 1303 Hongtong M=8 earthquake, Shanxi Province

Abstract

Based on the latest displacement of Huoshan piedmont fault, Mianshan west-side fault and Taigu fault obtained from the beginning of 1990’s up to the present, the characteristics of distribution and displacement of surface rupture zone of the 1303 Hongtong M=8 earthquake, Shanxi Province are synthesized and discussed in the paper. If Taigu fault, Mianshan west-side fault and Huoshan piedmont fault were contemporarily active during the 1303 Hongtong M=8 earthquake, the surface rupture zone would be 160 km long and could be divided into 3 segments, that is, the 50-km-long Huoshan piedmont fault segment, 35-km-long Mianshan west-side fault segment and 70-km-long Taigu fault segment, respectively. Among them, there exist 4 km and 8 km step regions. The surface rupture zone exhibits right-lateral features. The displacements of northern and central segments are respectively 6–7 m and the southern segment has the maximum displacement of 10 m. The single basin-boundary fault of Shanxi fault-depression system usually corresponds to M≈7 earthquake, while this great earthquake (M=8) broke through the obstacle between two basins. It shows that the surface rupture scale of great earthquake is changeable.