以塔里木盆地哈得逊地区东河砂岩滨岸相输导层为例,研究输导层的非均质对油气运移和聚集影响.利用沉积构型的研究方法将输导层的非均质结构解剖为9个级次;通过野外露头描述以及岩心物性资料,重点分析了东河砂岩7、8级输导层单元的非均质性.在同一级次的输导单元内,将输导层非均质类型划分为结构非均质和物性非均质两种类型;结合输导层非均质和流体分异发现两者有明显的对应关系.运用成藏数值模拟方法对东河砂岩的成藏动态过程进行模拟.综合以上研究成果,认为油气在滨岸相输导层内运移时,受储层非均质的影响油气的运聚具有时空不均一性.这种复杂的时空配置关系造成的复杂油水分布是倾斜的油水界面的主要成因.从古油藏到新的圈闭聚集成藏,输导层非均质性对这一过程的影响表现在运移和聚集两个过程,包括运移开始、运移调整、运移稳定、聚集开始和聚集结束五个阶段.两个过程五个阶段在输导层的不同位置发生.%To understand the influence of heterogeneity of sandy carrier bed of littoral facies on hydrocarbon migration and accumulation,a case study of the Donghe sandstone in the Hadexun area,Tarim Basin was conducted in this paper.The heterogeneous structure of the carrier bed was divided into nine grades based on the study of sedimentary architecture.The heterogeneity of grades 7 and 8 were further investigated through the outcrop description and core physical property analyses.In the same grade,heterogeneity types of carrier bed were divided into structural heterogeneity and physical property heterogeneity.The heterogeneity of carrier bed and fluid differentiation have an obviously corresponding relation. Numerical simulation shows the dynamic process of hydrocarbon accumulation in the Donghe sandstone reservoirs. Synthesizing all the results above, it can be concluded that the hydrocarbon migration and accumulation in the sandy carrier bed of littoral facies has heterogeneity,both temporally and spatially.This results in the complicated oil-water relationship, which is the major cause of the inclined oil-water interface. The heterogeneity influences the process of hydrocarbon migration and accumulation from paleo-oil pools to new traps in five stages:migration initialization,migration adjustment, migration stabilization, accumulation initialization and accumulation completion. Two processes and five stages occur in different positions of carrier bed.
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