摘要
单砂体平面、层内(小层韵律性)非均质性已不能满足高含水期、三次采油阶段的需求,其既不能揭示单砂体内部物性空间变化及分布,更忽略了单砂体内非渗透薄夹层(多<30cm)对储层非均质性的影响。文中提出按反映单砂体成因、形成微过程及内部结构的储层建筑结构(architecture)研究单砂体内部三维非均质性的思想,并结合曲流点坝单一侧积体沉积模式及其侧叠模式,建立了"渗透率向凸岸、向上减小的新月形楔状侧积体,逐一斜列侧叠,其间被非渗透侧积薄夹层隔开"的曲流河道砂体"建筑结构控三维非均质模式",揭示了以往忽视的、但对单砂体内部三维非均质性至关重要的不渗透薄夹层及其遮挡-阻流格架;也由此客观地揭示了单砂体内部物性基本单元(侧积砂体)及其三维分布规律,从而真正反映了单砂体内部三维非均质性的本质,并由此对单砂体内部渗流场、注入剂驱油和剩余油形成与分布产生重要影响,这将对高含水期、三次采油阶段及其以后的剩余油研究、预测具有重要意义。
The planar and intrastratal （layer rhythmicity） heterogeneity of monosandbody is unable to meet the demand in high water-cut stage and Tertiary phase. It cannot reveal the spatial variation and distribution of physical property in monosandbody, and it ignores the effect of impermeable thin interbeds （mostly less than 30 cm） in monosandbody on the reservoir heterogeneity. This paper proposes an approach for studying the three-dimensional heterogeneity, that is, to study the three-dimensional heterogeneity according to the reservoir architecture that reflects the origin of sandbody, the micro-process of formation and the reservoir texture. Combining the sedimentation model with the sedimentary stack of laterally-accreted body in meandering point bar, we establish a three-dimensional heterogeneous model of meandering channel sandbody controlled by architecture. This model features the lunate, wedge-shaped laterally-accreted body whose permeability is decreasing toward the convex bank and upward; these accreted bodies laterally stacking and dipping towards the channel migration direction at 5-15° angle one by one, and being divided by impermeable laterally-accreted thin interbeds. This model reveals the impermeable thin interbeds and barrier-restricted framework, which is important to the three-dimensional heterogeneity of monosandbody but has been ignored in previous models. It objectively reveals the basic physical property unit （the laterally-accreted sandbody） and its regular pattern of three-dimensional distribution in monosandbody, and truly reflects the nature of the three-dimensional heterogeneity in monosandbody. This would have important influence on the seepage field, the injeetant driving oil, and the generation and distribution of remaining oil in monosandbody. This would have a significant impact on the study and forecast of residual oil in high water-cut stage and tertiary phase as well as thereafter.
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2008年第1期57-64,共8页
Earth Science Frontiers
基金
中国石油天然气股份有限公司科技风险创新研究资助项目(油科函字(2004)32-KF3)
关键词
储层建筑结构
三维非均质性
曲流河道
单砂体
层内非渗透薄夹层
侧积泥岩
reservoir architecture
three-dimensional heterogeneity
meandering channel
monosandbody
impermeable thin interbeds in monosandbody
laterally-accreted mudstone
