叠前同时反演方法在流体识别中的应用

Application of prestack simultaneous inversion in fluid identification

(1.中国石油大学(北京)资源与信息学院,北京102249;2.中海石油(中国)有限公司北京研究中心,北京100027;3.科麦奇中国石油有限公司,北京100028;4.帕拉代姆技术(北京)有限公司,北京100023)

Faculty of Natural Resource & Information Technology,China University of Petroleum (Beijing),Beijing 102249,China

基于多角度道集和多尺度信息约束的叠前同时反演方法是利用多个角度的叠加数据体,将叠后波阻抗和叠前AVO属性整合到反演流程中,并将地震、测井、地质(包括构造倾角)等多尺度信息作为软约束条件参与反演的方法。应用迭代算法,同时反演出与岩性和含油气性相关的纵波阻抗、横波阻抗和密度等多种弹性参数,综合判别储层物性和含油气性,降低单纯利用纵波弹性阻抗反演的非唯一性,增强反演结果的稳定性和可靠性。综合利用颜色编码交会分析和三维可视化技术对众多叠前同时反演属性三维数据体在剖面和空间上进行解释,提高了对弹性反演属性的解释能力。将该反演方法和技术思路应用于新疆某油田M地区,优选XuWhite模型估算S波时差曲线,对4个不同角度的叠加数据体进行了叠前同时反演,使用AVO颜色编码交会分析技术预测了工区中砂岩和含油气性分布。结果表明,利用该方法能有效识别储层和流体。

Prestack simultaneous inversion is based on multi-angle gathers and multi-scale data confining,by using the stack data volumes from multi-angles,integrating poststack wave impedance and prestack AVO attributes into inversion workflow,and taking multi-scale information (such as seismic,geologic and logging data) as soft restraint condition,through iteration,to simultaneously inverse many elastic parameters (P-wave impedance,S-wave impedance and density),eventually discriminate reservoir properties and hydrocarbon bearing. The method decreases the multiplicity of inversion only by P-wave elastic impedance,strengthens the stability and reliability of inversion result. Color coding cross-plot and 3D visualization were comprehensively applied to interpret the 3D data volumes from prestack simultaneous inversion,which improves the interpretation capability for elastic inversed attributes. The technique and workflow were applied in M area. XuWhite modeling was optimized to estimate S-wave moveout,and carry out prestack simultaneous inversion on four stack data volumes with different angles,combined with AVO color coding cross-plot,the distribution of sandstone and hydrocarbon bearing were predicted. the result shows that the method can be used to effectively identify reservoir and fluid.