井中地震VSP观测系统正演模拟  

FORWARD MODELING OF BOREHOLE SEISMIC VSP OBSERVATION SYSTEM

作　　者：牛欢[1] 潘冬明[1] 周国婷[1] 

机构地区：[1]中国矿业大学资源与地球科学学院,江苏徐州221000

出　　处：《物探与化探》2013年第2期280-286,共7页Geophysical and Geochemical Exploration

摘　　要：在分析井中VSP地震观测系统特点的基础上,对观测到的地震波类型和特征作了阐释,分析了几种VSP模型(水平界面模型、倾斜界面模型、变偏移距模型、不同深度检波点模型)的射线追踪记录以及合成记录,利用射线追踪方法进行正演模拟,得到正演结果,并研究地震波的运动学特征。得出一些规律:钻孔穿过地层的数量等于合成记录上上行波和下行波的交点的数量;利用P波进行射线追踪和用转换波追踪其合成记录有差别,即转换波对VSP合成记录有影响;不同倾角的岩层对VSP上行波、下行波的走时特征和能量特征有影响;VSP合成记录的水平分量上会出现反极性现象,这与理论相一致。Based on analyzing the characteristics of borehole VSP observation system,the authors investigated the types and features of the observed seismic waves,analyzed ray-tracing and composite records of several VSP models（horizontal interface model,oblique interface model,meta-deviation distance model and detection point model）,conducted forward modeling by using the ray-tracing method so as to obtain the forward result,and studied kinematic characteristics of the seismic wave.Some regularities have been detected： the number of the strata penetrated by the drill hole is equal to the number of intersecting points between the ascending waves and the descending waves in the composite record;there exist differences between the composite ray-tracing record obtained by utilizing P wave and that obtained by utilizing the transform wave,which shows that the transform wave has some influence on VSP composite record;strata of different dip angles have influence on travel-time features of ascending wave and descending wave as well as the energy characteristics of VSP;there exist reverse polarity phenomenon on the horizontal component of VSP composite record,which is consistent with the theoretical phase.

关 键 词：井中VSP地震观测系统 射线追踪 正演模型 合成记录 

分 类 号：P631.4[天文地球—地质矿产勘探]