Identification Of Low-Grade Faults And Fine Interpretation Of Micro-Structures In The No.1 Area Of Gangdong Complex Fault-Block Oilfield

The study and practice show that the geological structure is one of the main controlling factors of the oil-water movement law in the complex fault-block oilfield.Therefore,the more fine structure interpretation is an important direction for remaining oil exploration of such reservoirs in the future.In this research,the NO.1 area of Gangdong oilfield is taken as the representative of complex fault-block oilfield,and focused on two aspects: data processing of seismic and well,and interpretation methods.Structure interpretation is combined with the deep learning technology to achieve finer interpretation including high precision,high accuracy,high reliability and high intelligent.In this research,the FCN-based method is highly integrated with the structure mode and expert experience of research area to identify the low-grade faults.And,on the basis of fault-system characteristics and statistical analysis,the level-6 fault is defined and identified.The high-precision fault identification attribute body can be converted into a 3D fault model,and the features of the fault are obtained.This lays a foundation for the quantitative characterization of faults in the whole area.This paper proposes different quantitative characterization methods for different levels of faults.The 3D characteristics of skeleton faults(above level 4)should be analyzed in detail.For the low-grade faults,pay more attention to the combination rule between the faults,and based on these rules to predicate the fault features by machine learning method.For example,predicating the displace of low-grade faults by XGBoost.In this study,the LSTM method is applied to realize the curve correction of logging data by the way of“stratigraphic sequence to sampling point”.And,proposing a fine stratigraphic division and correlation scheme combining well-log,seismic and fault in complex fault block area.Finally,drawing top surface structural maps of single sand bodies on the basic of stratigraphic division and identification of fault,and the distribution of forward micro-structures and low-grade fault is verified.Then,some suggestions are put forward for the oilfield development and adjustment in the future,based on the practice development of oilfield and effects of faults and micro-structures on oil-water movement.