滑塌浊积砂体精细地层划分对比方法——以大芦湖油田樊107块沙三段中亚段为例

Fine stratigraphic division and correlation of the slump turbidite sandstone—a case study of middle Sha3 member in block Fan107,Daluhu Oilfield.

大芦湖油田樊107块沙三段中亚段滑塌浊积砂体纵横向上连通性差、相变快,加大了小层对比的难度。综合地质、测井和地震3方面的资料,运用高分辨率层序地层学等时沉积的观点,建立了适合研究区的精细地层划分与对比方法。首先在区域不整合面识别的基础上,划分了长期基准面旋回;在井震精细标定标志层的基础上,在标志层的控制下,建立了中期基准面旋回等时地层格架;然后结合自旋回、相序递变规律进行短期基准面旋回识别,进而实现了沉积时间单元的划分与对比;最后在沉积时间单元内部结合沉积相研究了单砂体的连通方式。最终将大芦湖油田樊107块沙三段中亚段划分为4,5,6和7共4个砂层组,26个沉积时间单元,识别了5种单砂体连通类型,实现了单砂体的对比。

The sedimentary facies is semi-deep lake-slump fan in block Fan107 in Daluhu Oilfield.For turbidite sandstone the stratigraphic correlation is very difficult because of irregular distribution and large variability in lateral direction.Based on the theory of high-resolution sequence stratigraphy,the information of seismic,well logging and core data were analyzed and applied to the stratigraphic division and correlation.The long-term base-level cycle was recognized by the regional unconformity.The isochronous stratigraphie framework of middle-term base-level cycle was built according to the fine calibration of maker bed integrating wells with seismic data.The method of combining autocyclicity analysis with facies sequence was used to recognize short-term base-level cycles and depositional time cells.The lateral connectivity styles of single sandstone were established by researching of sedimentary facies.Middle Sha3 member in block Fan107 of Daluhu Oilfield was divided into No.4,No.5,No.6 and No.7 four sand groups,and 26 depositional time cells and 5 connectivity styles of the single sandstone.The result of stratigraphic division and correlation is feasible.