摘要
根据岩石薄片、扫描电镜、压汞、核磁共振、岩心、测井等分析和化验资料,对塔中顺9井区志留系柯下段储层特征进行研究。结果表明,研究区岩性主要为细粒岩屑砂岩和长石岩屑砂岩,具有成分成熟度低、结构成熟度中等的特点;储集空间以残余粒间孔为主,其次为次生孔隙和裂缝;储层物性较差,具有特低孔隙和超低渗透特征;孔隙结构参数具有分选系数中等、细歪度、高排驱压力、高中值压力、低中值半径、低退汞效率的特点,孔隙结构复杂;储层喉道半径小,孔喉比大,喉道是控制储层渗流能力的关键因素;储层的可动流体饱和度较低,渗透率是影响致密砂岩储层可动流体饱和度的重要因素。成岩作用是控制研究区柯下段储层物性的重要因素,压实作用、胶结作用为主要的破坏性成岩作用,溶蚀作用为主要的建设性成岩作用,成岩演化末期的储层基质孔隙度约为7.13%。利用储层物性和孔隙结构参数,可将顺9井区柯下段划分为Ⅰ,Ⅱ和Ⅲ类储层,其中Ⅰ类储层为相对优质储层。
The characteristics of S_1k^1 reservior in Shun9 well block of Tazhong were investigated based on the data from core analysis,log,magnetic resonance,rate-controlled mercury penetration,high pressure mercury injection,and observations of scanning electron microscope and thin section.The fine lithic sandstone and fine feldspathic lithic sandstone are the major lithology type of this reservoir which is characterized by low compositional maturity and medium texture maturity.The pore space types of reservoir mainly include the residual of primary intergranular pores,secondary intergranular pores and microfractures.The petrophysical properties of the reservoir are not favorable with low porosity and permeability.The pore structure is complex with medium sorting coefficient,gentle skewness,high displacement pressure,high median pressure,low median radius and efficiency of mercury withdrawal.It is the throat rather than the porosity that controls the permeability of the reservoir because of the small throat radius and high pore throat radio.Affected by the low permeability,the saturation of mobile fluid is low.The compaction and cementation are the key destructive diagenesis and the dissolution is the key constructive diagenesis.They are the major factors that affect the quality of the reservoir.The matrix porosity is 7.13%at the end of the diagenesis evolution of the reservoir.According to the petrophysical properties of reservoir and pore structure parameters,the S_1k^1 reservoir was classified into 3 types and type I is better than the others.
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2014年第4期42-45,113-114,共4页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项"碎屑岩层系大中型油气田富集规律与勘探关键技术"(2011ZX05002)
关键词
致密砂岩
储层特征
成岩演化
储层评价
塔中顺9井区
S_1k^1
reservoir characteristics
diagennesis evolution
reservoir evaluation
Shun9 well block of Tazhong
