Research On Fine Prediction Of Fu-yang Oil Layer In Shang'er Block,Daqing Oilfield

Channel sandstone is dominated in Fuyang pays in Songliao Basin,characterized by single bed thin,small difference between sand and mudstone and thin alternate layers overriding.The dissertion is a research on preditcation and estimation of favorable reservoirs in which the researched subject body is the Shang'er project.Based on the theory of deposition and seismic inversion,and appling the material of drilling,logging and high-resolution seismic data,the article identifies the small faults combining simibility technology and dip-steering technology,and predicts thin channel sandstone using spectral inversion,attribute analysis and prestack inversion,for dealing with two difficult points including complex fault development and hard identification of interbeded channel sandstone.At last,we come up with the spatial development characteristics of the reservoir and distribution law.The main contents are as follows:(1)For the fracture are well developed and spatial distribution of fracture is complex,the fine portray of fault is got using a variety of new technologies:the combination of coherence cube technology and inclination body,using diffusion filtering and median filtering to process seismic data.36 additional small faults are identified.Flat,profile and 3-D display are used to determine the charactreristics of spatial distribytion patterns of faults;we increase the trap area effectivly.After analying the distribution characteristics of the fault,we study the relationship of fault and the oil and gas reservoir.(2)The area meandered River-Delta-Lacustrine depositional system,which determines the reservoir is well developed:the strip,net distribution of thin channel sand,and strong heterogeneity and instability in lateral direction.The author studied the previous single well analysis and extracted various types of property,re-analyed sedimentary microfacies distribution in this area.Spectrum analysis is used to identify energy attenuation between different frequencies and identify the reserior.Thin interbedded property can be portrayed.Matching pursuit algorithm which shows high accuracy in recognition of thin interbedded is better than the continuous wavelet.How to improve the vertical resolution is the key research in the thin-layer reservoir prediction.Widess thoughts ?,8 is vertical resolution limit,but most of the actual situation is not what Widess model shows.With the development of the spectrum theory,spectral inversion technique is becoming a new bright spot in the thin-layer prediction techniques.This paper analyzes the development process of spectral inversion and its basic principle,and carries out the spectral inversion of seismic data.After processing of seismic data,which shows a higher vertical resolution,we can distinguish the thin layer,which can be used for high-precision seismic interpretation and identification of thin layer of sand bodies.In this paper,we use prestack,poststack data to carry out prestack elastic inversion and poststack resistivity inversion,and the results shows that both techniques has high vertical resolution.The inversion results are used to identify the channel sand body of Fuyang reservoir.Finally,we predict the favorable reservoir of Fuyang oil layer based on the channel sandstone identified by kinds of methods combined and relationship analysis between fault spatial distribution and reservoir forming rules.