层析成像技术在城市活断层探测中的应用  

Application of tomography inversion method in detecting active fault

作　　者：秦晶晶[1] 袁洪克[1] 何银娟[1] 季通宇 刘增祺 王宏伟[1] QIN Jing-jing;YUAN Hong-ke;HE Yin-juan;JI Tong-yu;LIU Zeng-Qi;WANG Hong-wei(The Geophysical Exploration Center of CEA,Zhengzhou 450002,China)

机构地区：[1]中国地震局地球物理勘探中心,郑州450002

出　　处：《地球物理学进展》2018年第5期2153-2158,共6页Progress in Geophysics

基　　金：洛阳市活断层探测与地震危险性评价项目资助

摘　　要：城市环境复杂、背景干扰较强以及浅表层改造较严重等因素,使得地震剖面探测深度范围有限,无法获取较浅层地表的地下结构信息.本文采用层析成像技术,充分利用地震记录中的初至波走时,对洛阳活断层浅层地震资料进行反演计算,获得了该剖面近地表速度分布和静校正量;并结合已有的钻孔地质资料对成果进行分析讨论.结果表明:层析成像技术不仅在一定程度上弥补了浅表层反射资料的缺失,还为后期的偏移和时深转换提供可靠的速度信息,同时还消除了近地表静校正量的影响,提高了地震资料的成像效果,具有较好的应用价值.The complexity of the urban environment,the strong background interference and the serious reconstruction of the superficial layers made the exploration depth range of the seismic section limited and the subsurface structure information of shallow surface can not be obtained. In this paper,we used the tomographic imaging technique taking advantage of the first-arrival travel time in seismic records to invert the Luoyang shallow seismic data and obtained the near-surface velocity distribution and static correction of this section. As well as,we analyzed and discussed the results based on the existing borehole geological data. The researches show that the tomography technique not only made up for the lack of shallow reflection data to a certain extent,but also provided the reliable velocity information for post-migration and time-depth conversion. At the same time,the tomography also eliminated the influence of near-surface static correction and improved the imaging effect of seismic data,which had a good application value.

关 键 词：层析成像 初至波 近地表速度结构 活断层 静校正 

分 类 号：P631[天文地球—地质矿产勘探]