低渗致密砂岩油藏水驱储层变化规律
The Variation Law of Water Flooding Reservoir in Low Permeability Tight Sandstone Reservoirs
石立华 1师调调 2廖志昊 3薛颖 4李禄胜2
作者信息
- 1. 陕西延长石油(集团)有限责任公司,陕西 西安 710065;陕西省特低渗透油气勘探开发工程技术研究中心,陕西 西安 710065
- 2. 陕西延长石油(集团)有限责任公司,陕西 西安 710065
- 3. 中国石油长城钻探工程有限公司,辽宁 盘锦 124010
- 4. 西安思坦仪器股份有限公司,陕西 西安 710065
- 折叠
摘要
针对低渗致密砂岩油藏水驱前后储层中黏土矿物及微观孔隙结构变化规律认识不清的问题,以鄂尔多斯盆地延长油田长 2 和长 6 储层为研究对象,运用铸体薄片、X衍射、高压压汞等实验方法,研究了储层岩石矿物类型及含量、黏土矿物类型及含量和微观孔喉结构特征,分析了水驱前后储层变化规律.研究表明:与长 2 低渗储层相比,长 6 致密储层微观非均质性更强;水驱后,长 2 储层中的伊/蒙混层和伊利石含量升高,绿泥石含量和伊/蒙混层比降低,长 6储层中伊/蒙混层含量、绿泥石含量、伊/蒙混层比均下降;当孔喉半径较大时,注入水对孔喉起改善作用,当孔喉半径较小时,注入水对孔喉起破坏作用;岩心渗透率越大,压力传播速度越快,注入水推进速度更快,出口端更易见水.该研究可为低渗致密砂岩油藏注水开发提供技术参考.
Abstract
To address the issues of unclear understanding of the variation law of clay minerals and micro-porosity structure within low permeability tight sandstone reservoirs before and after water flooding,the Chang 2 and Chang 6 Reservoirs in Yanchang Oilfield of Ordos Basin were taken as research objects.The types and contents of rock and clay minerals,the characteristics of microscopic pore throat structure are studied by using experimental methods such as casting thin sections,X diffraction and high pressure mercury intrusion,and the variation law of reservoirs before and after water flooding was analyzed.The results show that the microscopic heterogeneity of Chang 6 tight reservoir is stronger than that of Chang 2 low permeability reservoir.After water flooding,the content of illite/Mont-morillonite mixed layer and illite in Chang 2 Reservoir increased,chlorite content and illite/smectite mixed layer ra-tio decreased,and the content of illite/smectite mixed layer,chlorite content and illite/smectite mixed layer ratio in Chang 6 Reservoir decreased.When the pore throat radius is large,the injected water improves the pore throat.On the contrary,the pore throats are damaged by the injected water.The larger the core permeability is,the faster the pressure propagation velocity is,the faster the injected water advances,and the more water is visible at the outlet end.This study can provide technical reference for water flooding development of low permeability tight sandstone reservoirs.
关键词
低渗砂岩/致密砂岩/水驱/储层特征/微观孔喉变化/鄂尔多斯盆地Key words
low permeability sandstone/tight sandstone/water flooding/reservoir characteristics/microscopic pore throat variation/Ordos Basin引用本文复制引用
基金项目
陕西省自然科学基础研究计划(2023-JC-YB-423)
&&(2022JQ-290)
延长石油集团科技攻关项目(ycsy2022jcts-B-32)
出版年
2024
国家科技期刊平台
NSTL
万方数据