三维叠前深度偏移技术在西部复杂地区的应用与效果

三维叠前深度偏移技术是解决复杂构造的速度横向变化剧烈地区的地震资料成像问题的理想技术。应用三维叠前深度偏移处理软件ＧｅｏＤｅｐｔｈ，对我国西部Ｅ区的地震资料进行了三维叠前深度偏移处理，取得了良好的处理效果。其基本思路是：①在时间剖面上拾取速度层位，建立时间模型；②用相干反演法和速度转换法相结合逐层求取层速度，建立层速度－深度地质模型；③用剩余速度分析修改和优化地质模型；④选用克希霍夫积分求和法实现

Application of 3-D prestack depth migration to West-China complicated area and its effect

3-D prestack depth migration is an ideal seismic data imaging technique for theArea where there occur very complicated geologic structure and severe lateral velocity variation. GeoDepth softwares have been applied to 3-D prestack depth migration of seismic data in Eaarea of West China, and bring satisfactory effect. The essential procedure can be described in the following points:Design time model by picking up velocity horizons in time section.Construct interval velocity-depth model by using the interval velocitieswhich have been obtained layer by layer with the use of coherent inversion and velocity conversion methods.Improve geologic model through residual velocity analysis.Achieve the 3-D prestack depth migration after Kirchhoff summation.