绕射波探测浅层空洞的正演模拟与成像初探  

Forward Analysis on Diffraction Wave Applied to Detect Shallow Cavity

作　　者：张燕生 陆金波 ZHANG Yansheng;LU Jinbo(General Survey Institute,CNACG,Beijing 100039)

机构地区：[1]中国煤炭地质总局勘查研究总院,北京100039

出　　处：《城市地质》2020年第4期451-455,共5页Urban Geology

基　　金：浅层(0-200米)地下空间探测技术研究(ZMKJ-2018-3)。

摘　　要：利用传统的反射波地震勘探分辨率很难满足小尺度浅层地下空洞的探测需求,地震产生的绕射波却因其特有的传播特性,使得发现浅层地下空间中存在的小尺度异常成为可能。本文通过建立浅层地下空洞地质模型并进行地震波场正演分析,阐明绕射波能够对埋深20 m至50 m、异常尺度为2 m的空洞进行有效的刻画成像,从而说明,在地下工程(隧道、管线等)建设过程中,可以通过合理布设地震观测系统,运用绕射波地震勘探方法对浅层地下空洞进行较好地探测,提高城市建设的安全性。It is difficult to meet the needs of small-scale underground cavity detection for the resolution of the classical reflection seismology.However,diffractions generated from seismic wave propagation procedure would be more properly to detect the small-scale anomalies in the shallow underground space due to their unique propagation characteristics.This paper states that diffractions can effectively imagine the cavity with an abnormal size of 2m in the depth of about 20 m to 50 m,through modeling the near subsurface cavity and forwarding seismic wave.The forward modelling results show that diffraction wave can effectively describe the cavity with an abnormal size of 2 m in the buried depth of 20 m to 50 m.It shows that the diffractions exploration method is much benefit to detect shallow cavity by certain suitable seismic survey system in those city underground engineering(tunnel,pipeline,etc.)projects,even then guarantee the safety of urban construction.

关 键 词：绕射波 空洞异常 浅层勘探 地下空间 地下工程 

分 类 号：P631.4[天文地球—地质矿产勘探]