利用CAP方法反演了2011年1月19日安庆MS 4.8地震震源机制解。反演得到震级MW=4.1,节面I走向角16°、倾角74°、滑移角120°; 节面II走向131°,倾角33°,滑移角30°; 震源深度为3km。两个节面的走向与震中附近的宿松-枞阳断裂的走向相差较大,加之前人的地质考察结果显示,该断裂晚第四纪以来地震活动性较弱,故认为宿松-枞阳断裂是安庆MS 4.8地震发震构造的可能性较小,本次地震很可能是北北东向的隐伏断层活动的结果。

In this article，we have inverted local broadband waveform data to determine the foca1 mechanism of 2011 Anqing MS4. 8 earthquake． Our result shows that the best double couple solution of the MS4. 8 event is 16°，74° and 120° for strike，dip and rake angles respectively． The other nodal plane is 131°，33°，30°;the estimated focal depth is about 3km． The both strikes of the two nodal plane are significantly different with the strike of the Susong-Zongyang fault，which has a low level of seismic activity since Late Quaternary． This implies that this earthquake may not occur on the Susong-Zongyang fault，and we infer that a buried fault with strike of NNE may be the seismogenic structure of this event．

中国地震局地震预报司震情跟踪工作任务(2011020104)资助