相控多属性预测在元坝东砂体刻画中的应用

Application of Facies- control Multi-attribute Prediction to Sandbody Characterization in Eastern Yuanba Area

须家河组四段致密砂岩储层是川东北地区陆相层系重要的勘探领域,由于受到岩性复杂、物性差、地震反演参数敏感性差等多种因素的影响,常规储层预测难度大。为此,提出相控多属性储层预测方法,通过井上精细对比,确定川东北元坝东致密砂岩储层的优势发育段,结合手工追踪砂体展布确定其有利相带分布,在有利相带约束下,优选出地震平均能量、曲率体属性、平均波峰值属性和谱分解属性,融合这些属性,综合预测储层发育区。通过已钻井的对比,其储层发育区与钻井资料高度吻合。

As an important exploration domain of continental strata in northeastern Sichuan Basin, the Xujiahe 4 Member, a tight sandstone reservoir, is featured by complex lithology and poor petrophysical properties, and it is poorly sensitive to seismic inversion parameters, further resulting in large difficulties in a conventional prediction. So, a method of facies-control multi-attribute prediction is presented. By adopting this method, the tight sandstone reservoir with high quality is made clear; and then, combing with manual tracing sandstone distribution, the favorable facies belt distribution is determined; thirdly, the seismic average energy, curvature,average wave peak, and spectral decomposition are optimally selected; finally, merging these attributes together, some reservoirdeveloped areas can be predicted. The results obtained are highly coincident with those from drilling.