鄂尔多斯盆地蟠龙油田长6致密砂岩储层特征研究

Study on the characteristics of Chang-6 sandstone reservoirs in Panlong Oilfield,Ordos Basin

通过铸体薄片、扫描电镜、高压压汞等方法,对鄂尔多斯盆地蟠龙油田长6储层岩石学特征、孔隙类型、孔隙结构进行了研究。长6储层主要以长石砂岩为主,少量为岩屑长石砂岩。主要以残余粒间孔和长石粒内、粒间溶孔为主,孔隙度主要在3%～12%,均值为7.9%,渗透率中值为0.71×10^(-3)μm^2,是典型的致密砂岩储层。长6储层孔隙结构复杂,孔喉细小,根据压汞资料将长6储层细分为3种孔喉类型,并以Ⅲ类储层为主。

The petrological characteristics, pore type and pore structure of Chang 6 reservoir in Panlong Oilfield, Ordos Basin were studied by means of casting thin section, scanning electron microscopy and high pressure mercury injection. Chang 6 reservoir is mainly feldspar sandstone, a small amount of lithic feldspar sandstone. The main pore types are residual intergranular pores and intragranular and intergranular solution pores. The porosity is mainly 3%~12%, the average value is 7.9%, and the median permeability is 0.71 × 10^-3μm^2. It is a typical tight sandstone reservoir. Chang 6 reservoir has complex pore structure and fine pore throat. According to mercury injection data, Chang 6 reservoir is divided into three pore throat types, and the Ⅲ type reservoir is the main one.