基于强震动台阵记录的震源破裂长度实时估测方法  

Real-time estimation of rupture length of earthquake source based on records of strong motion array

作　　者：刘辰[1,2] 李小军 景冰冰[3,2] Liu Chen;Li Xiaojun;Jing Bingbing(Institute of Geophysics, China Earthquake Administration, Beijing 100081, China;College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, China;China Earthquake Risk and Insurance Laboratory, Beijing 100081, China)

机构地区：[1]中国地震局地球物理研究所,中国北京100081 [2]中国地震风险与保险实验室,中国北京100081 [3]北京工业大学建筑工程学院,中国北京100124

出　　处：《地震学报》2018年第3期387-398,共12页Acta Seismologica Sinica

基　　金：国家自然科学基金(U1434210;51421005);国家重点研发计划项目(2016YFC1402800)共同资助

摘　　要：本文提出一种通过小孔径台阵波束形成技术快速估测震源破裂长度的方法,同时提出了调整各台站相位的方法,即在每个台站的延时无法确定的情况下,近似地得到每个台站之间相位差的方法。在此基础上,利用自贡强震动观测台阵在汶川地震中得到的主震地震动记录进行了破裂长度的离线快速估测。结果表明,该方法的时效性较好,在地震动加速度峰值到来前约10 s时,便得到了断层破裂长度(约120 km)和相应破裂走向的估测结果,虽然此时的估测结果与最终估测结果(约230 km)有较大的偏差,但从实现快速地震预警的角度来看,还是有较好的实际意义。通过与前人的研究结果进行对比,结果显示该方法低估了东北方向的破裂长度,于是探讨了该现象产生的原因及可能的解决方案。最后对这种算法的计算速度进行了测试分析,结果表明通过并行计算该方法能够满足实时断层破裂长度估测的要求。We develop a fast rupture length estimation method by using small-aperture seismic arrays beam-forming technology,and proposed a method to adjust the phase of each station. By the method the phase difference of each station can be calculated approximately,when delay of each station cannot be determined. The result of Wenchuan earthquake outline test shows that the time efficiency of this method is good,for example,at about 10 s before the arrival of peak ground acceleration,the estimation result of rupture length is about 120 km. Although this estimation has a large deviation compared with the final estimation results（about 230 km）;however,from the point of view of fast earthquake warning,it still has good practical significance.By comparing with the previous research results,it is indicated that this method underestimates the rupture length in northeast direction,and the causes and possible solutions are discussed.Finally,the computational speed of the algorithm is studied,the results show that the method can meet the requirement of real-time fault rupture length estimation by parallel computing.

关 键 词：地震预警 波束形成技术 震源方位角反向投影 断层破裂长度 自贡台阵 

分 类 号：P315.2[天文地球—地震学]