辫状河河道砂体内部构型表征方法与层次结构解析

Configuration Method and Hierarchical Structure Analysis of Braided Channel

辫状河砂体一般垂向叠置厚度大,在稀疏井网条件下,如何揭示辫状河厚层砂体空间展布规律向来是砂体建筑结构分析中的重点。本文利用岩心、测录井等资料,结合古代露头以及卫星照片现代沉积等资料建立起来的辫状河地质知识库,采用垂向分期,平面划界的方法,对小层内的厚层辫状河道砂体砂体建筑结构进行分析,其中小层内井点处的辫状河道砂体需细分至单层,并依据已有的地质知识库和地质概念模型进行井间合理插值预测,从而最终实现单期河道平面延伸轨迹的追踪和对比,然后按单期沉积发育顺序,完成复合辫状河道沉积演化过程与历史重建。该研究成果有助于指导解剖地下河流相砂体砂体层次结构及不同成因砂体叠置规律,为后期深入勘探开发及水平井部署提供理论依据。

In general,multi-stage superimposed braided channel sandbodies have a large thickness,and under the condition of sparse well pattern,it is difficult for identification of configuration analysis and plane distribution.Based on core,logging combined with outcrop and satellite images data,the geological knowledge data-base is built up,meanwhile,using the methods of vertical stage-division,plane boundary-division the sandbody architecture is interpreted.The channel sandbodies of braided river from drilling well are divided into single layer and then the braided channel sandbodies from inter-well are interpolating estimated based on existing geological knowledge base and geological conceptual model in order to realize the correlation of single channel in the plane.According to the order of channel evolution,the depositional process of braided channel is reconstructed.Practical results show that the method has good applicability and can meet the production and practice requirement.Presentation of channel filling mode can provide the theoretical reference for infilled well pattern,horizontal well deployment and adjust perforation-profile.