摘要
基于常规物性、扫描电镜、铸体薄片、压汞测试等资料,对哈得逊油田东河砂岩的孔喉结构进行划分,选取各类型孔喉结构的典型岩心,通过微观刻蚀薄片驱替实验及水驱油过程的核磁共振、CT扫描研究微观剩余油不同尺度下的分布特征、赋存状态和动用机理。结果表明:研究区存在小孔细微喉-低渗储层、中孔细喉-中渗储层和大孔中喉-高渗储层。微观剩余油可分为单一孔喉尺度的原始状态型、孔内分散型、表面吸附型和角隅型剩余油,局部孔喉组合尺度的斑块状、多孔状和单孔状剩余油,岩心样品尺度的连片状富集、分散状富集和星点状富集剩余油。剩余油主要赋存于中、小孔喉内,赋存状态上分为离颗粒表面较远的游离态剩余油和颗粒表面的水驱难动用束缚态剩余油。随着孔喉结构的变好,孔内分散型剩余油比例有所增加,斑块状剩余油比例下降,剩余油星点状富集增强,束缚态剩余油逐渐减少。油层注水开发后,中、小孔喉内游离态的原始状态型剩余油比例最大,是后期重点挖潜对象,可以采用注微球封堵大孔喉后续水驱的方式进行开采,其潜力大小与游离态剩余油总量相近。
Based on conventional physical properties, scanning electronic microscope, casting slices, mercury injection test and other data, the pore-throat structure of Donghe sandstone in Hadeson oilfield is divided to select the typical cores of pore-throat structure in all types. The distribution characteristics, occurrence status and mobilization mechanism of microscopic remaining oil at different scales are studied by the nuclear magnetic resonance and CT scanning in micro etching thin-section displacement experiment and water-oil displacement process. The results show that the low-permeability reservoirs with micro-pore and tiny throat, mid-permeability reservoirs with meso pore-thin throat and high-permeability reservoirs with macro pore-medium throat exist in the study area. Microscopic remaining oil can be divided into the remaining oil at single pore-throat scale including original state type, intra-pore discrete type, surface adsorption type and corner stranded type, that at partial pore-throat combined scale characterized with plaque shape, multi-pore shape and single-pore shape, and that at the core sample scale with continuous enrichment, scattered enrichment and sporadic enrichment type. Remaining oil mainly occurs within meso-micro pore throat, divided by occurrence status into the remaining oil in a free state far away from grain surface and that in a bound state difficult to be mobilized by water flooding on grain surface. With the improvement of pore-throat structure, the proportion of remaining oil of the intra-pore discrete type is increased, while that of the plaque-shaped remaining oil is decreased, and the sporadic enrichment of remaining oil is enhanced, but the remaining oil in a bound state is gradually reduced. After the development of water flooding in reservoirs, the original remaining oil in a free state in the middle and small pore throat accounts for the largest proportion as the main target for later exploitation, which can be exploited by injecting microspheres to block the large pore thr
作者
余义常
徐怀民
高兴军
江同文
方惠京
孙廷彬
Yu Yichang;Xu Huaimin;Gao Xingjun;Jiang Tongwen;Fang Huijing;Sun Tingbin(Research Institute of Petroleum Exploration and Development, Beijing 100083, China;College of Geosciences, China University of Petroleum, Beijing 102249, China;PetroChina Tarim Oilfield Company, Xinjiang Korla 841000, China;Research Institute of Exploration and Development, Sinopec Zhongyuan Oilfield Company, Henan Puyang 457000, China)
出处
《石油学报》
EI
CAS
CSCD
北大核心
2018年第12期1397-1409,共13页
Acta Petrolei Sinica
基金
国家科技重大专项(2017ZX05030-001)
中国石油天然气集团公司重大科技专项(2017D-4406)资助
关键词
东河砂岩
孔喉结构
微观剩余油
多尺度
分布特征
赋存状态
Donghe sandstone
pore-throat structure
microscopic remaining oil
multi-scale
distribution characteristics
occurrence state
