1977年10月19日广西平果县城厢公社发生的5.0级地震,震中位于N23°23′12″、E107°32′12″,它发生在一个长期地震活动性较低的地区。主震发生后至当年12月14日共记录260余次余震;根据已确定的34次余震震中分布,大体呈北东东向分布(图1),由图可见,主震位于余震区的西北端,它显示出此次地震的破裂过程是由西北向东南方向扩展。余震区长约11公里,宽约7公里,由小台网确定的34次余震震源深度(图2),80％在9公里以内, On October 19, 1977, a magnitude 5.0 earthquake hit Chengxiang commune in Pingguo County, Guangxi. The epicenter was located at N23 ° 23’12 “and E107 ° 32’12” and occurred in a region with low long-term seismicity. A total of more than 260 aftershocks were recorded after the main shock to December 14 of that year; according to the epicenter distribution of the 34 aftershocks that have been identified, the distribution is generally northeast to east (Figure 1). As can be seen from the figure, the main shock is located northwest of the aftershock zone It shows that the rupture of the earthquake is from northwest to southeast. The aftershock zone is about 11 km long and 7 km wide. The aftershock focal depth of 34 aftershocks identified by Xiaotai Network (Figure 2) is 80% within 9 km,