【作者】 胡明顺；

【导师】 董守华； 潘冬明； 陈圣恩；

【作者基本信息】 中国矿业大学 ， 地质资源与地质工程， 2013， 博士

【摘要】 为提高煤层气储层井中地震勘探精度，本文在传统的VSP地震数据处理成像方法基础上，系统地研究了煤层气RVSP地震勘探数据成像方法。目前，传统的井中地震处理成像方法主要存在问题有：①RVSP地震资料存在严重的管波和多次波影响；②传统的RVSP速度分析手段无法获取炮排列以下地层的速度信息；③当前RVSP地震数据成像方法成像方法与速度分析相互孤立，成像质量不及应有的理想效果。围绕上述几个问题，本文深入开展了如下研究：①详细推导了均匀介质、水平层状介质和连续变化介质条件下的RVSP反射波时距曲线方程和反射点计算公式；②根据典型的煤层气储层地质特征，数值模拟研究RVSP观测系统下地震波传播规律，分析RVSP记录波场特征和噪声来源及性质，研究高保真上行反射波分离与去噪方法；③研究基于双程声波波动方程的RVSP叠前逆时偏移成像方法，分析偏移噪音来源及特点，研究偏移噪音压制方法，研究改进逆时偏移边界条件构建，解决大存储空间要求与成像质量等问题；④研究基于RVSP共反射点道集和共炮点道集的速度谱分析方法，获取最大激发深度以下地层速度信息，分析基于不同速度分析方法的RVSP-CDP变换叠加成像特点及其适用范围；⑤研究抽取RVSP数据的CDP道集，利用地面地震数据处理思想和流程，进行速度谱分析、动校正、剩余静校正和叠加偏移的RVSP完全等效地面处理成像新方法。通过上述研究，本文主要取得了如下几点重要研究成果：①提出了基于非线性自适应随机边界与PML吸收边界相结合的混合边界条件RVSP叠前逆时偏移方法；②提出了基于地面地震时距曲线方程和RVSP时距曲线方程的共反射点道集和共炮点道集的相干速度谱分析方法；③提出了基于RVSP-CDP道集抽取的完全等效地面处理成像方法。利用以上研究成果，对沁水盆地万宝山地区煤层气RVSP地震试验数据进行精细处理，通过对原始数据的波场和噪声特征分析，实现了反射波的有效分离，并利用层析静校正技术对检波点静校正量进行了校正，完成RVSP-CDP道集抽取、速度分析、剩余静校正，动校正和叠加成像处理，取得了与同测线位置不同地震勘探方法和数据处理方法相比最佳的成像效果。初步形成了一套适合煤层气RVSP地震数据处理成像方法，对进一步提高煤层气储层井中地震勘探精度具有重要的实际意义。更多还原

【Abstract】 To improve the capability of coalbed methane abundance prediction by boreholeseismic exploration, enhance the level of coalbed methane exploration anddevelopment technology, complement China’s energy structure and reduce theincidence of coal mine gas outburst accident quickly, this dissertation, based on thetraditional VSP seismic data processing and imaging methods, systemically studiedCBM RVSP seismic data imaging method. Currently, the main problems of thetraditional borehole seismic processing and imaging includes:①RVSP seismic datahas serious impact due to tube wave and multiple wave;②Traditional RVSP velocityanalysis methods cannot build accurate velocity model of the stratums under thedeepest shot position in well;③Existing RVSP seismic data imaging methods arealmost isolated with velocity analysis, so image quality is not as good as the desiredeffect should be.To address the issues described above, this dissertation carried out in-depthseveral study points as following:①RVSP reflected wave time-distance curveequations and reflection point calculation formulas in the homogeneous medium,horizontally layered medium and continuous change medium have been derived indetail.②According to the typical CBM reservoir geology characteristics, seismicwave propagation under observation system of RVSP has numerically simulated,besides the wave field characteristics of RVSP record and the source and nature ofnoise also have been analyzed to study how to separate the up reflected wave andsuppress noise effectively.③Based on two-way acoustic wave equation RVSPpre-stack time migration, as well as analysis of migration noise sources andcharacteristics, boundary condition of RTM has been studied to suppress themigration noise and improve the imaging quality by solving the issue of large storagespace requirement of RTM.④New velocity analysis methods have been studied toobtain velocity information of the stratums under the maximum excitation depth andthe characteristics and scopes of RVSP-CDP transform stack imaging, based oncommon reflection point gathers and common shot gathers speed spectral analysismethod.⑤A completely new imaging method has been studied for RVSP data, basedon the RVSP-CDP gathers extraction, which could apply surface seismic dataprocessing ideas, such as velocity spectral analysis, NMO correction, residual staticsand stack migration.Based on the above research contents, this dissertation has made some important achievements as follows:①Hybrid boundary condition for RVSP pre-stack timereverse migration is proposed, which combines the adaptive stochastic nonlinearboundary and PML absorbing boundary conditions.②Coherent velocity spectrumanalysis methods, based on common reflection point gathers and common shotgathers, as well as surface seismic and RVSP time-distance curve equations, areproposed.③RVSP perfectly equivalent surface seismic data processing and imagingmethod is proposed, based RVSP-CDP gathers extraction.Finally, using the above research results, a set of experimental CBM RVSP data,acquired in Wanbaoshan regions of Qinshui Basin, was analyzed and processednarrowly. By the analysis of the characteristics of wave field and noise of the originaldata, reflected waves are separated effectively, and receiver static correction iscompleted by applying tomographic static correction technique, lastly RVSP-CDPgathers extraction, velocity analysis, residual static correction, NMO correction andstack imaging process are realized, this imaging result is the best profile comparedwith the imaging result from surface seismic data on the same survey line and theresult achieved from the same RVSP data but by a simple processing method.Through the above research achievements, a set of CBM RVSP seismic dataprocessing and imaging technology processes is eventually formed preliminarily. Insummary, these achievements of this study has practical significance in furtherenhancing the level of CBM abundance prediction by borehole seismic exploration.更多还原