相干层速度反演在叠前深度偏移中的应用  

Application of Coherent Velocity Inversion in Pre-stack Depth Migration

作　　者：汪勇[1,2] 顾汉明[1] 范宝仓 

机构地区：[1]中国地质大学(武汉)地球物理与空间信息学院,湖北武汉430074 [2]长江大学地球物理与石油资源学院,湖北荆州434023 [3]中海油服物探事业部数据处理中心,天津300451

出　　处：《石油天然气学报》2011年第4期56-60,116,共5页Journal of Oil and Gas Technology

基　　金：国家"十一五"科技重大专项(2008ZX050000230401)

摘　　要：常规时间偏移和叠后深度偏移均不能解决崎岖海底地区地震成像问题,而叠前深度偏移是解决这一问题的有效方法。叠前深度偏移的效果取决于建立的速度-深度模型的精度,而相干层速度反演方法与深度域层析成像相结合,有能力得到更为准确的速度场。基于模型,分析了影响相干层速度反演精度的因素:上层速度反演的结果会明显地影响到下层速度反演的结果和叠前深度偏移成像的质量;解释层位时,要把关键层位解释出来,不能忽略重要的上覆地层,即构造复杂时,应逐层反演。Conventional time migration and post-stack depth migration could not be used to solve the problem of rugged seabed seismic imaging,while pre-stack depth migration was an effective way to solve the problem.The effect of pre-stack depth migration depended on speed-depth of the model,while the coherent velocity inversion combined with the tomography could obtain more accurate velocity field.Based on the model,the factors influencing the coherent velocity inversion accuracy are analyzed,the upper velocity inversion results would significantly affect the results of the lower velocity inversion and pre-stack depth migration imaging quality;the important layer must be explained,the importance of the overlying strata can not ignored,when the structure is complicated,layer-by-layer inversion should be carried out.

关 键 词：相干层速度反演 叠前深度偏移 层位解释 剩余速度 

分 类 号：P631.44[天文地球—地质矿产勘探]