鄂尔多斯盆地盘古梁西长6段储层主控因素分析

Analysis of main controlling factors of Chang 6 reservoir in West Panguliang area, Ordos Basin

盘古梁西长6段油藏是陕北近年来提交探明储量和开发建产的重要区域。文中对盘古梁西长6段油层组储层岩石学特征、孔渗特征、微观孔隙结构特征及类型进行了深入分析,结果表明:该区长6段储层属三角洲前缘亚相沉积,储层具有成分成熟度偏低、结构成熟度中等的特点,储集空间主要为残余粒间孔和粒间、粒内溶孔及长石溶蚀形成的铸模孔;影响储层储集性能的主控因素较多,包括沉积微相、成岩作用、非均质性等多个方面;对储层发育影响最大的成岩期主要位于中成岩A期—中成岩B期;绿泥石膜残余粒间孔相、长石溶蚀相和浊沸石溶蚀相是最有利储层发育的成岩相带;通过微观非均质性研究,可区分出5种驱油类型。

Based on the analysis of lithological characteristics, porosity and permeability characteristics, micro-pore structure characteristics and types of Chang 6 reservoir in West Panguliang area, the results show that the sedimentary environment of Chang 6 reservoir is a delta front. Reservoir characteristics take on lower compositional maturity and medium textual maturity. The reservoir space types include residual intergranular pores, secondary corrosion pores, moldic pores and so on. The sedimentary microfacies, diagenesis and heterogeneity are main control factors for the reservoir properties. The diagenetic period of affecting reservoir development is stage A-B of middle diagenesis. And the gain-coating chlorite facies, feldspar corrosion facies and laumonite corrosion facies are favorable diagenetic facies belts for reservoir development. Five oil displacement types are distinguished by studying reservoir microscopic heterogeneity.