广角地震波场特征分析  

Analysis of the wide angle seismic wave field character

作　　者：张智[1] 张艳瑾[1] 董超[1] 李飞[2] 王海燕[2] 

机构地区：[1]广西隐伏金属矿产勘查重点实验室,桂林理工大学地球科学学院,桂林541004 [2]中国石油塔里木油田分公司勘探开发研究院,库尔勒841000

出　　处：《地球物理学进展》2013年第3期1171-1182,共12页Progress in Geophysics

基　　金：国家自然科学基金(41274070;41021063;40804017;41074033;40974025);国家科技专项项目(SinoProbe 02-02-02)联合资助

摘　　要：地震宽角反射/折射方法主要是利用壳内与上地幔顶层的广角反射信息重建地壳上地幔结构,是研究地壳上地幔结构构造最有效的方法之一.同时,宽角地震接收到的超临界角的广角反射信息,相对于临界角之内的反射信息必定存在着随偏移距变化的时移现象.本文通过构建地壳模型采用交错网格有限差分方法合成广角地震记录,并从理论地震图上分别用传统射线方法和考虑时移影响的方法标定了震相走时,分析了广角反射的地震波场特征,揭示了地震资料中的广角效应,继而分析了广角信息存在对接收波场的响应影响.The seismic wide-angle reflection/refraction method is the one of the most effective methods for probingthe crustal and upper mantle structure. It mainly uses the wide-angle reflection information from the boundary in thecrust and the top boundary of the upper mantle to reconstruct the crust and upper mantle structure. At the same time, we think relative to the pre-critical angle reflection information the post critical angle reflection information that received by wide-angle seismic data exits a time shift effect with the offset variation, and then it must cause the error for velocity analysis and structure image, we studied the features of the wide-angle seismic wave field through building the crust model to know the wide-angle influence on crust velocity image, through building crust model, we labeled the travel time for all the phases by ray tracing method and remove wide-angle effects method, it revealed the wide-angle effect exists in the seismic data.

关 键 词：宽角地震反射 广角效应 超临界角 相移 

分 类 号：P315[天文地球—地震学]