云南地区复杂地震各向异性分析  

Analysis of complex seismic anisotropy in Yunnan region

作　　者：盛敏汉[1] 张怀[1] 周元泽[1] 石耀霖[1] 

机构地区：[1]中国科学院大学地球科学学院中国科学院计算地球动力学重点实验室,北京100049

出　　处：《中国科学院大学学报（中英文）》2015年第6期775-782,共8页Journal of University of Chinese Academy of Sciences

基　　金：中国科学院重点部署项目(KZZD-EW-TZ-15-3)资助

摘　　要：地震各向异性可以反映地壳和上地幔形变信息.SKS震相由于近乎垂直入射,具有良好的横向分辨率.本文收集云南地区大量地震资料,提取并分析SKS分裂结果,发现研究地区各向异性很复杂,南北差异较大.进一步利用双层地震各向异性模型分析KMI台下方可能存在的双层各向异性特征:上层快波偏振方向130°,延迟时间0.2 s,而下层快波偏振方向90°,延迟时间0.9 s,与观测结果吻合较好.The deformation information of crust and upper mantle can be obtained from seismic anisotropy. SKS wave has good transverse resolution because of its almost vertical incidence. We collected a mass of seismic data in Yunnan region and calculated and analyzed the result of SKS wave splitting. Complex anisotropy and an obvious difference between south and north parts were found in this region. Then two-layer anisotropy model was used to analyze the data at KMI station,and a possible two-layer result which fits the observation data well was obtained. The splitting parameters are 130° and 0. 2 s for the upper layer and 90° and 0. 9 s for the lower layer.

关 键 词：SKS 云南地区 双层各向异性 

分 类 号：P315.3[天文地球—地震学]