基于界面约束法的曲流河点坝内部构型建模

基于Petrel软件和界面约束法，提出了曲流河点坝内部构型建模方法，该方法以点坝内部构型模式和构型解剖研究成果为基础，生成以曲面分布的侧积层顶、底界面，再通过多级界面联合约束方法在点坝内部建立起储层结构模型，实现点坝内部构型的精细表征。为便于后期的数值模拟，建立了模型网格非均匀粗化的方法，解决了模型网格数与侧积层精度之间的矛盾。通过大港油区某曲流河点坝对建模方法的有效性进行了验证。结果表明，该方法建立的模型可以很好地体现河道、点坝及侧积层等不同级别构型单元的空间分布，同时模型网格数大幅降低，由粗化前1 776 500个网格数减少至672 896个，减少了62.1%。模型计算储量与实际储量误差为1.84%，计算累积产油量、累积产水量与实际值的误差分别为0.3%和0.03%，能反映油藏实际情况。

Study on characterization of point bar architecture based on surface constrain

A new surface constrain modeling method is proposed herein for the lateral accretion shale beds of point bar sand by using Petrel. In order to characterize the internal configuration of point bar, top and bottom boundaries of the lateral accretion shale beds distributing with curved surface are created based on the patterns and analysis results of point bar architecture, then the reservoir architecture model is established in the point bar sand by the method of multi-order surface constrain. For ease of numerical reservoir simulation, we designed the method of nonuniform grid upscaling to ensure the accuracy of the laterally-accreted mudstone model and reduce the grids. Then, the validity of the modeling method is validated in a point bar sand of Dagang oilfield. The results show that the modeling can reflect the spatial distribution of different levels of architectural element such as channel sand body, point bar and lateral accretion interbeds, and the result can characterize the internal configuration of point bar and reflect the actual situation in the reservoir.