储层预测技术在子洲地区开发评价中的应用

Application of Reservoir Prediction Technology to Development Estimation in Zizhou Area

勘探表明子洲地区山2段储集砂体为三角洲前缘水下分流河道和河口坝沉积,是榆林气田含气主砂带向东南的自然延伸,与榆林气田具有类似成藏条件。岩石物理研究表明,随着含气饱和度的增加,山2砂岩的纵波速度先减少后增加,而密度随饱和度增加而减小,密度对于区分含气砂岩是敏感的。同时正演分析表明吸收系数可作为该地区含气性预测的一个敏感参数,处理结果显示与已知井有较高的吻合程度。

Exploration operations show that the reservoir sandbody of Shan-2 Formation in Zizhou area belongs to both delta-frontal distributary channel and distributary mouth bar deposition. In addition, the sandbody is the main gas-bearing sand belt in Yulin gasfield, which extends southeast-ward. Moreover, it has similar reservoir-forming conditions to those in Yulin gasfield. Petrophysical research illustrates that, along with an increase of gas saturation, P wave velocity in Shan-2 sandstone decreases at first and then increases whereas density decreases. Density is sensitive to classification of gas-bearing sandstone. Simultaneously, forward analysis indicates that the absorption coefficient may be a sensitive parameter to have a gas-bearing prediction in Zizhou area. And the processed result indicates that it is in high agreement with the given well.