碎屑岩储层构型分级方案与研究方法探讨

Discussion on architecture classification scheme and research methods of clastic reservoir

为了完善碎屑岩储层构型级次划分方案,并更好地应用于油田开发,从大港油田不同沉积类型储层构型研究的实际出发,通过建立以储层构型为基础的三维地质模型,并开展数值模拟,认识储层构型控制的剩余油分布,并对构型研究精度提出要求。将构型分级与地层划分分级、沉积微相分级有机结合和对应,重新确定储层构型分级方案,在此基础上提出储层构型研究的思路、内容和方法。结果表明:这种构型划分方案更明确,6级构型界面对应复合沉积体构型单元。平面上对应复合曲流带或复合辫流带,由2个以上单一复合体构成;剖面上为小层或砂层组,内部由多个单砂层组合而成,单砂层之间发育泥岩隔层。该方法应用于大港官80断块枣Ⅱ、枣Ⅲ油组,划分和表征7,8,9级构型单元(复合河道、单一沉积单元、增生体),对特高含水阶段密井网开发油田的构型研究具有明显优势。

In order to improve the architecture classification scheme of clastic reservoir and better apply it to oilfield development,based on the study of reservoir architecture of different sedimentary types in Dagang Oilfield,by establishing three-dimensional geological model and numerical simulation based on reservoir architecture research,the residual oil distribution controlled by architecture was recognized,and the accuracy of reservoir architecture research was required.The classification scheme of reservoir architecture was redefined by combining and corresponding stratigraphic classification with sedimentary microfacies classification.On this basis,the ideas,contents and methods of reservoir architecture research system were put forward.The results show that this reservoir architecture classification scheme is much more explicit,the sixth-order architecture interface corresponds to the composite sedimentary formation unit.On the plane,it corresponds to composite meandering zone or composite braided flow zone,which is composed of more than two single complexes;on the profile,it is composed of small layers or sand layers,and the interior is composed of multiple single sand layers,and mudstone interlayer is developed between the single sand layers.The scheme was applied to ZaoⅡand ZaoⅢoil formations in Guan 80 fault block of Dagang Oilfield,and the architecture units 7,8 and 9(composite channel,single sedimentary unit and accretion body)were divided and characterized,which have obvious advantages in the study of the archi-tecture of dense well pattern development oilfield in ultra-high water cut stage.