隧道三维Kirchhoff偏移成像影响因素分析  

Analysis of influencing factors about 3-D tunnel Kirchhoff offset imaging

作　　者：蔡盛[1] CAI Sheng(China Railway SIYUAN Survey and Design Group Co.,Ltd.Wuhan 430063,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,武汉430063

出　　处：《物探化探计算技术》2023年第1期8-16,共9页Computing Techniques For Geophysical and Geochemical Exploration

基　　金：中铁第四勘察设计院集团有限公司科研项目(2019K026);国铁集团科研开发项目(P2022G054)。

摘　　要：Kirchhoff偏移成像法是目前最灵活、高效的三维叠前偏移方法,其不受观测系统的限制,计算效率高,不需要很精确的速度模型也能得到较精确的偏移成像结果。在这里采用有限差分法实现了三维复杂介质弹性波场数值模拟,设计有效的三维观测系统并生成模拟数据,进行偏移成像计算,并系统分析了速度模型、走时计算、数据主频、干扰噪声、地质体形态等因素,对偏移成像精度的影响情况。其分析对比结果,对隧道三维Kirchhoff偏移成像算法优化与外业施工具有指导意义,有利于提高三维地震反射波法超前地质预报的精度与准确度。The Kirchhoff offset imaging method is currently the most flexible and efficient three-dimensional laminated offset method,which is not limited by the observation system,has high computational efficiency,and does not require a very accurate speed model to obtain more accurate offset imaging results.In this paper,the finite difference method realizes the three-dimensional numerical simulation of the tunnel seismic wave.We get analog data and calculate offset imaging according to the three-dimensional observation system.On this basis,we thoroughly analyze the speed model,travel-time calculation,data frequency,interference noise,geometric morphology,and other factors and their impact on imaging accuracy.These analysis results can help optimize the three-dimensional kirchhoff offset imaging algorithm and instruct the tunnel's construction.All this can help to improve the accuracy of the three-dimensional superior geological forecast.

关 键 词：Kirchhoff偏移成像 地震波 地质预报 影响因素 数值模拟 

分 类 号：P631.4[天文地球—地质矿产勘探]