High - resolution sequence stratigraphy has been studied and base - level cycle interface has been recognized for the beach - bar reservoirs in the upper part of the fourth member of the Shahejie formation in the Boxing oilfield of Donying depression by using drilling, coring and logging data. The studied section is divided into 1 long - term cycle, 6 medium - term cycles and 25 short - term cycles. The short - term cycles can be divided into upward deepening asymmetrical cycle, upward shoaling asymmetrical cycle, and upward deepening then shoaling symmetric cycle, thereby built up a framework of high resolution sequence stratigraphy. It is found that sands had developed in both rising and falling semi - cycle of the long - term base - level cycle, near the rising semi - cycle of the medium - term base - level cycle, and near the transforming interface from falling to rising, I. E. The initial flood surface of long - , medium - and short - term base - level cycles, where sands are thick and with good petrophysical property. Sands had not developed near the maximum flood surface from rising to falling cycle. The distribution of sands in short - term cycles shows evident difference among different medium - term base - level cycles.%利用钻井及岩心、测井、录井等资料,对东营凹陷博兴洼陷博兴油田沙四上亚段滩坝相储层进行了高分辨率层序地层学研究,识别基准面旋回界面.将研究层段分为1个长期基准面旋回、6个中期基准面旋回、25个短期基准面旋回.将短期旋回分为向上变深非对称型短期旋回、向上变浅非对称型短期旋回和向上变深再变浅对称型短期旋回,从而最终建立起工区高分辨率层序地层框架.发现砂体在长期基准面旋回上升、下降半旋回均有发育,中期基准面上升半旋回附近砂体较发育,处于长期、中期、短期基准面旋回的从下降到上升的转换面即初始湖泛面附近砂体发育,单层较厚,物性较好;由上升到下降的最大湖泛面附近砂体不发育,短期旋回地层在不同中期基准面旋回地层中的砂体展布特征差异明显.
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