埕北断阶带沙河街组油气运移动力学过程模拟分析

Simulation of hydrocarbon migration dynamics in Shahejie Formation of Chengbei fault step zone

在对渤海湾盆地埕北断阶带沙河街组含油气系统油气地质条件认识的基础上,运用盆地模型方法恢复研究区的盆地演化过程、相应的油气成熟范围和不同时期的运移动力条件。重点分析了研究区内不同输导体的孔隙度、渗透率等物性特征,用开启概率和砂地比分别表征断层和砂岩输导体的连通特征。采用以逾渗理论为基础的油气运聚模拟方法,在根据实际资料建立的二维输导格架模型上实现运移动力和通道的耦合。模拟结果显示出研究区沙河街组目的层段的油气运移路径及其油气运移相对流量,结合其他油气地质条件确定张东东构造带、张东构造带、庄海12—庄海9×3井地区等为有利勘探目标区。

Based on the understanding of geological conditions of petroleum systems in Shahejie Formation of Chengbei fault step zone, Bohaiwan basin, the evolution of the basin, hydrocarbon maturity, and dynamic conditions for hydrocarbon migration are successfully reconstructed through basin modeling, some physical properties such as the porosity and permeability of different pathway systems in the area are studied, and the connectivity of faults and sandstone carriers are quantified by the opening probability and net-to-gross ratio respectively. Hydrocarbon migration and accumulation modeling methods based on the percolation theory are used to realize the coupling of migration dynamics and pathways in the two-dimensional carrier framework model built on real data. The results reveal the hydrocarbon migration path and its relative flow rates in the target intervals of the Shabejie Formation. These study results, in combination with other geological conditions, are successfully used in identifying the prospective target zones, including eastern Zhangdong structural belt, the Zhangdong structural belt, and area around the Well Zhuanghai-12 and Well Zhuanghai-9×3.