【摘要】 利用铸体薄片与场发射扫描电镜观察,分析南襄盆地泌阳凹陷核桃园组三段致密砂岩储层储集空间;基于高压压汞技术和分形理论,对致密砂岩储层进行分类与分级。结果表明:研究区致密砂岩储层孔隙系统可划分为小孔(孔隙直径<0.1μm)、过渡孔(孔隙直径为0.1～1.0μm)、中孔(孔隙直径为1.0～3.0μm)和大孔(孔隙直径>3.0μm)。根据储层中不同类型的孔隙所占比例,可将致密砂岩储层分为4类,Ⅰ类(以大孔为主)、Ⅱ类(以中孔为主)、Ⅲ类(以过渡孔为主)和Ⅳ类(以小孔为主)。根据不同微观孔喉参数与储层物性的相关关系,可将致密砂岩储层分为4级,Ⅰ级储层孔隙度>10.0%,渗透率>1.000×10-3μm2;Ⅱ级储层孔隙度为5.0%～10.0%,渗透率为(0.200～1.000)×10-3μm2;Ⅲ级储层孔隙度为2.5%～5.0%,渗透率为(0.030～0.200)×10-3μm2;Ⅳ级储层的孔隙度<2.5%,渗透率<0.030×10-3μm2。利用储层分级评价标准选取最优质储层,为致密砂岩储层的油气勘探与开发提供指导。更多还原

【Abstract】 Through the casting thin sections as well as field emission scanning electron microscope,characteristics of the tight sandstone reservoir space in 3 rd member of the Hetaoyuan Formation in the Biyang Sag of the Nanxiang Basin have been analyzed.The tight sandstone reservoir was classified and graded based on high pressure mercury injection technology and fractal theory.The results show that a division method for micropore pores(less than 0.1μm),transitional pores(0.1～1.0μm),mesopores(1.0～3.0μm)and macropores(greater than 3.0μm)within tight sandstone reservoir in the study area was established.According to the volume percentage of various types of pores in the reservoir,the tight sandstone reservoirs were divided into Ⅰ,Ⅱ,Ⅲ and Ⅳ categories:category Ⅰ(mainly with macropores),categoryⅡ(mainly with mesopores),categoryⅢ(mainly with transitional pores),categoryⅣ(mainly with micropores).Further according to the correlation between different microscopic pore throat parameters and reservoir physical properties,the tight sandstone reservoirs are divided into four grades:the porosity of gradeⅠis greater than 10.0%,and the permeability of gradeⅠis greater than1.000×10-3μm2;the porosity of grade Ⅱ is 5.0% ～10.0%,and the permeability of grade Ⅱ is(0.200～1.000)×10-3μm2;the porosity of gradeⅢis 2.5%～5.0%,and the permeability of gradeⅢis(0.030～0.200)×10-3μm2;the porosity of gradeⅣis less than 2.5%,and the permeability of gradeⅣis less than 0.030×10-3μm2.The optimum reservoir is selected by the standard of division,which is aimed to provide guidance for the order of tight oil and gas development.更多还原