鄂尔多斯盆地南部本溪组气藏储层特征研究

通过铸体薄片、扫描电镜、高压压汞等分析化验手段,对鄂尔多斯盆地南部本溪组储层特征进行综合研究。结果表明,障壁岛-泻湖沉积是研究区本溪期主要的沉积相类型之一,本溪组气藏储层为潮道砂体和障壁砂坝砂体,含气砂体不受局部构造控制,为岩性气藏。该区本溪组储层岩性主要为中-粗粒石英砂岩,少量细砂岩和砾岩。根据分析结果本溪组储层孔隙度平均为2.9%,渗透率平均为0.8141×10^-3μm2,表明储层属于特低孔-特低渗储层。储集空间主要以原生粒间孔隙和粒间孔为主,其次为长石溶孔,喉道类型主要以微喉道为主。

Reservoir Characteristics of Benxi Formation in the South of Ordos Basin

With the methods of thin section observation, scanning transmission electron microscope and pressure mercury testing, Benxi formation reservoir characteristics of Ordos basin were studied. Research results show that, Barrier Island - Lagoon is one of the main sedimentary types of Benxi in study area, Benxi formation gas reservoirs is tidal channel and barrier dam sand. Gas-bearing sand, which is lithological gas reservoirs, is not controlled by local structure. In the area, Benxi formation is mainly consisted of medium-coarse grain quartz sandstone with a small amount of fine-grain sandstone and conglomerate. The average porosity of the reservoir is 2.7%, and the average permeability is 0.8141×10^-3μm2, which belongs to extremely low porosity and permeability reservoir. The main types of reservoir space are primary intergranular pores and intergranular pores, followed by feldspar dissolved pores. The main type of throat is micro throat.