鄂尔多斯盆地杭锦旗探区二叠系低孔渗储层主控因素分析  

MAIN CONTROLLING-FACTOR ANALYSIS OF PERMIAN LOW POROSITY AND LOW PERMEABILITY RESERVOIRS IN HANGJINQI EXPLORATION AREA IN ORDOS BASIN

作　　者：张琴[1,2] 唐玄[1,2] 庞正炼[3] 

机构地区：[1]中国地质大学海相储层演化与油气富集机理教育部重点实验室,北京100083 [2]中国地质大学能源学院,北京100083 [3]中国石油勘探开发研究院,北京100083

出　　处：《大庆石油地质与开发》2011年第3期45-50,共6页Petroleum Geology & Oilfield Development in Daqing

基　　金：基金项目：国家重点基础研究发展规划项目（2005CB422108）资助.

摘　　要：鄂尔多斯盆地北部杭锦旗地区低孔低渗的储层特征及成因是目前研究的热点。以杭锦旗地区上古生界二叠系储层为研究对象，对多组岩心的孔渗性进行测定，显示杭锦旗地区二叠系储层为低孔低渗的致密储层。通过对大量岩心测试数据、镜下薄片及扫描电镜等结果进行分析，认为低孔低渗储层的形成由沉积、煤系地层排酸溶蚀、压实及胶结等作用综合控制。近物源的冲积扇一河流沉积体系形成了研究区低成分成熟度和结构成熟度的储层岩石学特征，为形成低孔低渗储层提供了物质基础；煤系地层早期形成的酸性水对储层矿物进行溶蚀，并改变颗粒之间的接触关系，降低了储层抗压强度，使得储层在后期压实过程中孔渗降幅加剧；压实成岩作用使储层的孔渗性随岩层埋深增大而大幅降低；黏土、硅质及钙质胶结成岩作用镶嵌颗粒边缘，填充粒间剩余孔隙，进一步使储层物性变差。The characteristics and origin of low porosity and low permeability reservoirs in Hangjinqi area in north Ordos Basin are the hot spot of current study. The Permian reservoirs in Upper Palaeozoic have been studied, and the porosity and permeability properties of multi sets of cores are measured, showing that the Permian reservoirs in Hangjinqi area are the tight ones with low porosity and low permeability. Through the analysis of many core testing data, microscopic sections and scanning electron microscope results, it is believed that the formation of low porosity and low permeability reservoirs is controlled by sedimentation, acid discharge corrosion in coal measure strata, compaction and cementation comprehensively. The alluvial fan-fluvial depositional system near source supply has formed the reservoir lithology characteristics of low compositional and textural maturity in the studied area, providing the material base for the formation of low porosity and low permeability reservoirs; the acidic water early formed in coal measure strata corroded reservoir minerals, altered the contact relation among particles, reduced the compressive strength of reservoirs, and made the porosity and permeability dropping amplitude intensive during the late compaction ; the compaction diagenesis reduced the porosity and permeability properties of reservoirs greatly with the increase of formation burial-depth, clayey, siliceous and calcareous cementation diagenesises inlayed particle edges, the remaining pores among particles were filled, which caused reservoir physical-properties to be poorer.

关 键 词：杭锦旗探区 二叠系 低孔低渗储层 沉积作用 成岩作用 

分 类 号：TE122.2[石油与天然气工程—油气勘探]