大庆油田长春岭背斜带扶余油层沉积相特征

Characteristics of Depositional Facies of Fuyu Reservoirin Changchunling Anticlinal Zone,Daqing Oil-Field

大庆油田长春岭背斜带扶余油层沉积微相类型主要是三角洲前缘亚相带内的水下分流河道微相、分流间湾微相和席状砂微相。水下分流河道微相类型比较复杂,共发育有两大类:一是单期河道的正粒序型;二是多期河道叠置型,其中多期河道叠置又可以进一步划分为进积型、加积型、退积型。由于本区河道类型比较多,导致了本区的砂体展布具有复杂性,且由于河道砂体类型不同导致了砂体的连通性差,进而导致油气水分布的复杂性。扶余油层重矿物组合以高含锆石、石榴石为特征,与松辽盆地南部长春—怀德沉积体系的重矿物组合相似,与西南部保康沉积体系高含锆石、低石榴石的重矿物特征不同,进而判断本区受南部物源控制为主,东部物源控制为辅。

The depositional facies of Fuyu reservoir in Changchunling anticlinal zone, Daqing Oil-Field is dominated by submerged distributary channel, interdistributary bay and sheet sand micro-facies in delta front sub-facies. The submerged distributary channel is relatively complex, which can be divided into two types, one characterized by normal grading of single-period channel, another characterized by multi- period superimposed channels （among which can be divided into prograding, aggrading and retrograding）. Many types of channels result in complex distribution of sandbody and poor connection among sandbodies, which furthermore resulting in the complex distribution of oil, gas and water. Heavy mineral assemblage in Fuyu reservoir is characterized by high contents of zircon and garnet, which is similar to that of Changchun- Huaide depositional system in southern Songliao basin, different from that of Baokang depositional system （high content of zircon and low content of garnet） in southwest basin, inferring that the deposits are mainly sourced from the southern basin, secondly from the eastern basin.