川东北地区飞仙关组鲕滩储层的主控因素

Main Control Factors of Oolitic Beach Reservoir in Feixianguan Formation of Northeast Sichuan Basin

川东北地区飞仙关组鲕滩储层丰富,储层物性以普光气田为最好,龙岗次之,元坝再次之。通过3个区块在沉积、构造及成岩作用等方面的对比研究,来探讨川东北地区飞仙关组鲕滩储层的主控因素。研究结果表明,飞仙关组鲕滩储层主要受沉积相、构造活动、成岩作用及多因素匹配等制约。其中沉积相是基础,控制储层有利的岩石类型及分布;构造活动是桥梁,可改善成岩环境,促进成岩作用发生;成岩作用是关键,可改变岩石的原始结构和构造,促使孔隙形成及演化;多因素匹配好则可形成优质储层。在3个区块中只有普光气田具备了以上各种有利条件,且多因素匹配良好,从而形成了优质储层。

The oolitic beach reservoirs were rich in Feixianguan Formation of Northeast Sichuan Basin.Physical property of Puguang Gas Field was the best,the next was Longgang Gas Field and the third was Yuanba Gas Field.In these three blocks,the sedimentation,tectonism and diagenesis,the major controlling factors of reservoir were discussed through contrast.The research indicates that the oolitic beach reservoir is the constrained by sedimentary facies,tectonic activity and diagenesis and other factors.Sedimentary facies is the foundation controlling the rock types and distribution of reservoir.Tectonic activity is the bridge which can improve the diagenetic environment.Diagenesis is the key which can change the original structure and promote the pore formation and evolution.So the good quality reservoirs can form with co-activities of those factors.In the three blocks,only Puguang Gas Field has the favorable conditions to form quality reservoirs.