Abstract：It is difficult to work for most prestack narrow azimuth seismic data using conventional fracture prediction methods,which is suitable for wide azimuth seismic data.In order to solve the problem,we present a new method for fracture prediction on prestack narrow azimuth data with standard deviation statistics in this paper.As we all know,seismic wave propagation in isotropic and anisotropic media generates certain AVO (amplitude variation with offset) difference.The difference can be subdivided into two aspects:A.Difference between AVO curves with different incident angles if the azimuth is same; B.Difference between AVO curves with different azimuths if the incident angle is same if the incident angle is same.First we construct a background model of the study area based on logging data and rock physical model analysis.Then we stack narrow azimuth data to obtain stacked azimuth gathers data.After that we collect the difference between AVO curve of seismic data and AVO curve of the background model at every sampling point.Finally we use this standard deviation of the difference to characterize the fracture development at the sampling points.Real data application in Bohai shows that more than 80% fractures predicted by the proposed method are coincident with logging data interpretation.
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