河流相沉积储层地震精细预测方法研究与应用—以渤海湾盆地冀中坳陷古近系河道砂为例

Research and application of detailed seismic prediction in fluvial reservoirs—an example from the palaeogene channel sand in the Jizhong Depression,the Bohai Bay Basin

崔永谦 秦凤启 卢永和 杜维良

Cui Yongqian Qin Fengqi Lu Yonghe Du Weiliang

河流相沉积砂岩是陆相断陷常见的储层类型。由于河流改道频繁,砂、泥岩交互发育且横向变化快,造成地震反射连通性差,加之受分辨率限制,储层预测难度较大。以渤海湾盆地冀中坳陷中部研究区为例,进行了层位的精细标定和等时地层对比下的精细解释,进行优选提取地震属性并进行三维可视化立体雕刻;研究薄层的调谐频率,并利用分频研究结果预测河道平面分布;构建合理的地质模型,优选参数进行拟声波反演取得较高精度的预测结果。

Fluvial sandstone reservoirs are common in continental fault depressions.They are characterized by vertical alternating of sandstone and mudstone and lateral rapid change of lithofacies caused by frequent river diversion.These features lead to discrete seismic reflection.This,in addition to the limitation of seismic resolution,increases the difficulty of reservoir prediction.Taking the study area in the central Jizhong Depression of the Bohai Bay Basin as an example,we studied fine seismic interpretation based on accurate horizon calibration and isochronous stratigraphic correlation.Based on that,we optimized extraction of seismic attributes and built up 3D visualization model.Frequency tuning for thin layers was performed and the results of frequency division were used to predict river channel distribution in plane.We also set up rational geological models and performed pseudo-sonic inversion with optimized parameters to obtain high-precise reservoir prediction results.

10.11743/ogg20090519