【作者】 王玉贵；

【导师】 王彦春；

【作者基本信息】 中国地质大学（北京） ， 地球探测与信息技术， 2009， 博士

【摘要】 Walkaway VSP技术是VSP(垂直地震剖面)技术的一种,它是一种变偏移距激发、井中接收的二维VSP技术。该项技术目前尚未发展成熟,国内外仍处于研究阶段,尤其是资料处理中的偏移成像技术,目前应用的VSPCDP叠加成像方法建立在水平层状介质假设基础之上,克希霍夫积分偏移成像方法依赖于简单速度模型,这两种方法都无法满足实际复杂介质的需要。本论文对Walkaway VSP技术进行了较为全面的研究,详细论述了该技术的基本原理、观测系统设计方法、资料采集方法、资料处理方法以及成果资料解释应用方法。在研究过程中,重点研究了Walkaway VSP资料处理方法,针对具体的观测系统进行了静校正方法研究;对三分量合成方法进行了研究,指出了直角坐标系三分量合成方法对Walkaway VSP方法的局限性,应按地震波的传播方向和偏振方向进行非直角坐标系的坐标旋转;对波场分离方法进行了研究,成功分离出较为单纯的上行波场;对反射波成像方法进行了研究,改进了波场外推的波动方程照明成像方法,将常规偏移孔径转换成了VSP井中照明范围,消除了速度精度原因造成的成像偏差。论文的创新之处在于:(1)Walkaway VSP技术的观测系统设计方法。通过设计多排炮点激发、提升井中检波器的观测系统,弥补了井中检波器级数的不足,扩大了井中观测井段。(2)波场分离技术。在不同道集中用不同方法对波场进行分离、去噪,得到较为单纯的上行波场,为后续成像质量的提高创造了条件。(3)反射波成像技术。对波场外推的波动方程成像方法进行了改进,用VSP井中照明范围代替普通的偏移孔径,消除了速度精度原因造成的偏差,使得反射波得到很好归位。(4)通过对Walkaway VSP技术的综合研究,形成了一套完整的适合松辽盆地的Walkaway VSP技术实现流程,对其它地区也有很好的借鉴意义。应用以上方法,在松辽盆地古深2井进行了实际资料采集、处理试验,两条线均取得较好的试验效果。这充分验证了所研究方法的合理性。本论文的研究表明,Walkaway VSP技术在松辽盆地具有很好的推广应用前景。更多还原

【Abstract】 Walkaway VSP is one of VSP (Vertical Seismic Profile) technique. And it is a 2D VSP technique developed from Offset VSP, which shoots along varying offset and receives in well. This technique is not mature yet, so it is still in the stage of researching inland and abroad. Especially the migration imaging technology in data processing, the VSPCDP stack imaging is based on the assumption of Horizontal layered media and the migration imaging of Kirchhoff integration is heavily dependent on simple velocity model.Both of them are not able to meet the needs of the actual complex medium.The basic principles of walkaway VSP technique,the method of the geometry designing, data acquisition, data processing, and resulting data interpretation and application were discussed detailedly in this paper based on the comprehensive study on Walkaway VSP technique.The researching work was mainly focused on the method of data processing to Walkaway VSP data during the study.To specific geometry,the study about static correction method has been conducted.At the same time,the study of the method about synthetic of 3 components was conducted.The localization of the synthetic method of 3 components in Cartesian coordinate system for Walkaway VSP method was pointed out.A rotation of Non-Cartesian coordinate system following the propagation direction and the polarization direction of seismic wave should be applied in the future. The wave field separation methods have been studied and successfully isolated pure and simple up-going wave field. Meanwhile, reflection wave imaging method has been studied.The wave equation illumination imaging method based on wave field extrapolation was enhanced. This method converted conventional aperture into VSP illumination range.And the imaging bias caused by the accuracy of velocity is eliminated.The innovations of the paper: (1) The geometry design method of Walkaway VSP technology.Through the design of the geometry with multi-row shooting and lifting the geophones in well, solved the problem of deficiencies of geophone levels and expanded the paragraph of observation in wells. (2) The wave field separation technique. Through separating wave field and removing noises in the different gathers, received a more pure up-going wave field and laid a good foundation for following imaging. (3) The reflection wave imaging technology. The wave equation imaging method based on wave field extrapolation was enhanced.With the illumination range in wells of VSP instead of conventional wave equation migration aperture, the reflection wave was migrated better.(4)Trough the integrated study of Walkaway VSP technology,a integrated Walkaway VSP technique realized flow was formed and guidable meaning to other aera was obtained.The method mentioned above was applied to well GuShen-2 in Songliao Basin. Field data acquisition and processing were carried out, the good result has been obtained for both of the testing lines. It verified the rationality of this method.The study of the paper implies that there will be a good prospect for the application and extension of Walkaway VSP technique in Songliao Basin.更多还原