采用江苏省数字地震台网记录的地震波形资料,利用震源位移谱低频水平与拐角频率计算了2000～2010年江苏及邻近地区561个ML≥1.5中小地震视应力值。结果 显示,江苏及邻近地区的地震视应力平均值为0.91 MPa,与中国大陆的平均水平相当。视应力与震级无明显的线性关系,在震级相对较大时表现出一定的高震级对应高视应力的特点。视应力高值地区主要集中在江苏中部至南黄海海域,次高值集中分布在郯庐断裂带中南段的苏鲁交界地区、安徽段固镇至定远附近地区和肥东、巢湖一带,反映了以上地区较高的地震活动水平及地壳应力状态。不同区域ML2震级档视应力的差异性基本反映了区域地质环境、构造活动等特征的差异。
Based on the earthquake data recorded by Jiangsu Digital Seismic Network, we calculate apparent stress value of 561 ML≥1.5 medium and small earthquakes in Jiangsu and its adjacent area from 2000 to 2010 by using low frequency level of source displacement spectra and corner frequency. The results shows that the average value of apparent stress of the earthquake is 0.91 MPa in Jiangsu and its adjacent area, and which is the same as the average value in China mainland. There is not obvious linear relation between apparent stress and magnitude, however, it shows that the large magnitude corresponds to the high apparent stress when the magnitude is relative large. The high value area of apparent stress is mainly concentrated from central Jiangsu to the south Yellow Sea, and the sub-high value area of apparent stress is mainly distributed at the junction of Jiangsu and Shandong Provinces, the area around Guzhen-Dingyuan of Anhui segment and the area of Feidong and Chaohu in the south middle segment of Tanlu Fault zone, which reflects the earthquake activity and the crustal stress state is higher in these areas. The difference of apparent stress of ML2～2.9 earthquakes in different areas basically reflects the diversity of regional geological environment and tectonic activity etc..
