【作者】 王勃；

【导师】 刘盛东；

【作者基本信息】 中国矿业大学 ， 地球探测与信息技术， 2012， 博士

【摘要】 矿井巷道掘进安全受到前方断层破碎带、陷落柱、采空区、冲刷带及煤厚突变区等多灾害源控制，对其进行超前预测预报已成为当前研究热点，然而现有矿井地球物理勘探精度难于满足掘进施工的实际地质需求，为保障复杂地质条件下巷道安全、高效生产，开展全空间条件下反射波法精细超前探测研究显得十分必要。本文从三分量地震信号的实时偏振分析出发，基于“面波与体波极化程度差异”，引入偏振系数因子；根据“纵横波传播方向与质点振动方向正交差异”，引入主极化方向因子；按照“同类波与转换波速度差异”，引入相干因子。联合三个因子，构建调制函数融合到叠前偏移中，结合相干叠加及绕射偏移原理，提出了一种全空间条件下集波场分离、偏移成像于一体的极化偏移。针对二维、三维空间成像特点，完成了极化偏移程序设计，并基于Visual C++.net平台开发了PsFilter1.0数据处理系统。为验证极化偏移成像效果，本文相继展开了数值模拟、物理模拟及现场探测实验。在不同产状的单、多个异常界面超前数值模拟实验中，最大偏移距地震道不同类型的反射波单周期时窗长度内偏振分析结果，验证了纵、横波质点主极化方向与波行进方向存在正交差异特征。巷道迎头前方不同位置、产状及组合的地质异常界面成像效果证实：基于S变换的时频分析法确定时窗的二维极化偏移，可有效消除P-P波、SV-SV波成像的上下对称假象；根据同类波（P-P、SV-SV波）与转换波（P-SV、SV-P波）速度差异，二维极化偏移可有效压制转换波及干扰波。针对三个同倾向异常界面模型，进行了四种偏移方法、两种观测系统的对比实验，得出：极化偏移与传统叠前绕射偏移、Kirchhoff积分偏移、逆时偏移相比，异常界面收敛性强、方向分辨率高，解决了在巷道有限空间下由于偏移孔径小而导致的对称成像病态问题，且极化偏移在线性观测系统下便可实现准确定量评价。在水槽界面模型超前探测实验中，四种不同倾角异常界面的极化成像结果表明二维极化成像可有效判定异常体的位置、倾角、倾向；在巷道空间的岩体模型实验中，测线前方异常体空间轮廓收敛效果证实了三维极化偏移可显著提高地震反射波法成像的空间分辨率。根据矿井实际，研制出了一套井下安全、快捷的雷管震源及六分量传感器装置，该装置为极化偏移技术提供了一种实用的激发接收方式，山西、河南、江苏典型矿区多灾害源的现场探测对比实验，结果表明极化偏移技术能够为巷道超前预报提供必要的技术参数。更多还原

【Abstract】 The driving safety in the laneway is frequently controlled by multiple disaster sources,which include fault fracture zone, water-bearing body, goaf, collapse column, and so on.The advanced prediction research is becoming a hotspot. But existing measuring precisionof mine geophysical exploration is hard to meet the practical requirements of geology.Therefore, In order to protect roadway safe and efficient production under complicatedgeological conditions, it is thorough necessary to carry out the subtly advanced predictionof reflected wave method in the whole space.This paper start from the relationship between the real-time polarization analysis ofseismic wave, based on the polarization coefficient difference between surface wave andbody wave, polarization coefficient factor is introduced. In light of the orthogonaldifference between P wave and S wave, principal polarization direction factor is introduced.According to the velocity difference between surface similar wave and converted wave,coherent coefficient factor is introduced. A polarization modulation function is introducedon the basis of computation factors.Based on the coherence stack and diffraction stackmigration, A polarization migration that integrates wave-field separation and migrationimaging is proposed. Considering the characteristics of2-D and3-D space imaging, thepolarization migration programming is completed and PsFilter3.0data processing systemis developed based on the platform of Visual C++.net. Numerical simulation, physicalsimulation and field test are successively carried out in this paper for the sake of verifyingthe effect of polarization migration.In the experiments of advanced prediction numerical simulation with differentorientation single and multiple abnormal interface, the polarization analysis results withintime window lengths of single period of different types reflection wave groups of themaximal offset seismic trace show the orthogonal difference characteristics ofcompressional wave and shear wave main polarization direction and path dirction of wave.Geology abnormal interface imaging effect of different positions, diverse occurrence,various combinations in the front of driving face verify that, the upper and lowersymmetric false appearance of P-P wave and SV-SV wave can be filtered effectively by2Dpolarization migration based on time-frequency analysis method to get time window;2Dpolarization migration, which is got from mutual coherence weighted computing that isbased on the velocity difference of P-SV and SV-P, can availably suppress converted wave and interference wave. From the different migration methods and the contrast experimentsof various observation system of three-layer geological anomaly model with the sametendency, we can find that, compared with traditional pre-stack refraction scanningmigration, Kirchhoff integral migration, and reverse-time migration, the abnormal interfaceof polarization migration has the characteristics of good convergence and high directionresolution, avoiding imaging ill-conditioned problem which is caused by small migrationpore impacted from roadway space, and accurate quantitative evaluation of polarizationmigration can be realized only in linear observation system.In the advanced physical model experiment in the flume, the polarization migrationimaging results of abnormal interface with four different dip indicates that2D polarizationmigration imaging can efficiently judge the position, dip and tendency of anomalous body;In the rock mass model experiment considering the influences of roadway, the convergenceeffects of the anomalous body’s spatial contour verify that the spatial resolution of seismicreflection wave method can be obviously improved by3D polarization migration.According to the practical condition in the coal mine,, multi-component seismicsignal with wider frequency band and reliable multiply component is provided by speciallymade detonator source and six-componet sensor for polarization migration. The detectioncontrast experiments of typical mining areas in Shanxi, Henan and Jiangsu indicate thatpolarization migration technology can achieve the advanced prediction effects of highaccuracy and resolution.更多还原