2000年云南姚安地震余震区的速度和衰减结构层析成像分析  

Tomography and Analysis of Velocity and Attenuation Structure for the 2000 Yaoan Aftershock Area in Yunnan

作　　者：张杰卿[1,2] 刘杰[3] 周龙泉[3] 

机构地区：[1]中国地震局地震预测研究所,北京100036 [2]天津市地震局,天津300201 [3]中国地震台网中心,北京100036

出　　处：《地震》2009年第3期126-135,共10页Earthquake

基　　金：国家科技支撑计划项目(2006BAC01B02-01-04);国家重点基础研究发展规划项目(2004CB418406)联合资助

摘　　要：文中根据2000年云南姚安6.5级地震后,流动数字化地震监测台网记录到的地震序列走时和波形资料,采用震源位置和速度结构联合反演的方法,反演了震源区的VP、VS和QS的三维结构。层析成像结果显示,姚安6.5级地震发生在低VP、高QS扰动异常的边缘,大部分余震均发生在高、低VP、QS过渡区域内。VP的低值异常表明姚安震区存在一条NWW向断裂带,且异常深度达到10 km左右。该文通过研究地震序列的分布特征并结合震源区速度结构和衰减结构的特点,进一步探讨了姚安地震的发震构造。Three-dimensional Vp, Vs and Qs structures in the focal area of the 2000 Yaoan M6.5 are obtained by the simultaneous inversion method of travel time and waveform data recorded by a temporary seismic network installed after the earthquakes. The tomography results show that the earthquake occurred at the brim of the area with low-Vp and high-Qs disturbance anomalies. Most of the aftershocks are in sandwiched VP and Qs zones between higher and lower values. The obvious low-VP anomalies in the focal area demonstrate the existence of the NWW fault and the anomalies is down to the depth of about 10 km. The seismogenic structure of Yaoan earthquake area are further discussed by combining the characters of the aftershock distribution with the velocity and attenuation structures in the focal area.

关 键 词：速度结构 衰减结构 层析成像 地震断裂带 姚安地震 

分 类 号：P315.7[天文地球—地震学]