摘要
储集砂岩孔隙的差异演化过程会影响储油空间变化以及砂岩油的赋存变化,厘定致密砂岩孔隙的差异演化过程及其成因有利于油田调整后期开发方案。以南梁地区延长组长4+5段致密油储集砂岩为研究对象,通过气测岩心物性、高压压汞数据结合岩石薄片、SEM等镜下显微观测,分析长4+5^(1)段与长4+5^(2)段的物性及孔隙特征差异,定性、定量表征孔隙差异演化特征,并探讨其成因及孔隙差异演化对致密砂岩油分布规律的影响,以期为研究区调整致密砂岩油开发方案提供依据。研究表明,差异性胶结作用是长4+5^(1)段与长4+5^(2)段储集砂岩孔隙差异演化的主要因素,早期胶结作用发育导致长4+5^(2)段储集砂岩致密化程度高,晚期胶结作用发育则导致长4+5^(1)段储集砂岩后期抗压实作用强,储油空间比长4+5^(2)段存留的更多。孔隙的差异演化导致长4+5^(1)段储集砂岩宏观平均厚度及有效厚度均高于长4+5^(2)段,发育粒间孔、晶间孔、长石溶孔的复合孔隙类型和低方解石含量、高铁方解石含量、高绿泥石含量的储集砂岩有利于致密砂岩油富集。
The differential evolution of reservoir sandstone pores affects the change of oil storage space and the occurrence of sandstone oil,and clearing the differential evolution process and origin of dense sandstone pores is beneficial to the later development scheme.Taking Chang 4+5 Member of the Yanchang Formation in Nanliang area as the research object,and the differences in physical properties and pore characteristics between Chang 4+5^(1)Member and Chang 4+5^(2)Member were analyzed through the physical properties of the core of the gas measurement,the high-pressure mercury intrusion data,and microscopic observations such as rock thin sections and SEM.The pore differential evolution was qualitatively and quantitatively characterized,and the causes and the influence of the different evolution of the pore space on the distribution of tight sandstone oil were explored,providing a basis for adjusting the development plan of tight sandstone oil in the study area.The study shows that differential cementation is the main factor in the differential evolution of reservoir sandstone pores of Chang 4+5^(1)Member and Chang 4+5^(2)Member.The development of early cementation leads to a high degree of densification of Chang 4+5^(2)Member,while the development of late cementation leads to a strong compaction resistance of Chang 4+5^(1)Member in the later stage,and the oil storage space is more than that of Chang 4+5^(2)Member.The evolution of pore differences leads to the fact that the average thickness and effective thickness of the reservoir sandstone in Chang 4+5^(1)Member is higher than that in Chang 4+5^(2)Member,and the development of intergranular pores,intergranular pores and feldspar soluble pores,as well as the reservoir sandstone with low calcite content,high iron calcite content,and high chlorite content,is conducive to the enrichment of oil in the tight sandstone.
作者
王宝
刘军锋
陈寿
张伟
吴雨风
Wang Bao;Liu Junfeng;Chen Shou;Zhang Wei;Wu Yufeng(No.2 Oil Production Plant of Changqing Oilfield Company,Qingyang 745400,China;School of Earth Science and Resources,Chang′an University,Xi′an 710054,China)
出处
《能源与环保》
2025年第2期121-130,共10页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
基金
国家自然科学基金青年科学基金项目(41502137)。
关键词
鄂尔多斯盆地
致密油
长4+5段
南梁地区
孔隙差异演化
控藏作用
Ordos Basin
tight oil
Chang 4+5 Member
Nanliang area
evolution of pore differences
effect of reservoir control
