志丹油田海子塌区长6储层特征研究

Research on reservoir characteristics of Chang 6 oil layer in Haizita block,Zhidan oilfield

通过利用岩石镜下薄片、铸体薄片、压汞实验、扫描电镜、物性数据资料对志丹油田海子塌区长6储层特征及储层的成岩作用分析。结果表明:研究区岩石类型以长石砂岩为主,孔隙类型主要为剩余粒间孔隙和溶蚀孔,孔喉结构以小孔隙-微喉道类型为主,孔隙度平均值为8.6%,渗透率均值为0.28 mD,属于低孔隙度、特低渗透率储层。储层成岩作用中压实作用为中等程度,胶结作用以方解石胶结为主,溶蚀作用为长石颗粒的粒间溶蚀及粒内溶蚀。

Based on the data of sandstone thin section,casting thin section observation,mercury penetration experiment,scanning electron microscope and reservoir property data,this study researched the reservoirs characteristics and the diagenesis of the reservoir properties of Chang 6 oil bearing formation in Haizita area.The result shows that the rock type is feldspathic sandstone,residual intergranular pores and dissolution pores are majority of pore types.The small-pore micro-throat is the major type of pore throat structure.The average value of porosity is 8.6%and the average value of permeability is 0.28 mD.These values indicate reservoir of research area can be classified in low porosity and ultra-low permeability reservoir.In the diagenesis of the reservoir,the compaction is moderate,calcite cementation occurs frequently,the intergranular dissolution and intragranular dissolution of feldspar particles are general existence.