OBN shear wave noise suppression based on P and z component Radon transform and unsteady adaptive subtraction
In OBN seismic data acquisition,the coupling between the geophones and the seafloor often leads to the fact that the z-component of the land inspection receives shear wave noise.Shear wave noise seriously inter-feres with the subsequent processing,imaging,interpretation,and reservoir monitoring of OBN data.Besides,the frequency band and curvature of the shear wave noise are very similar to the effective signal,which is diffi-cult to suppress through conventional methods.Therefore,an OBN shear wave noise suppression method based on parabolic Radon transform and unsteady adaptive subtraction is proposed.Firstly,this method trans-forms the P-component and z-component data of the OBN data into the r-q domain through the parabolic Radon transform method and utilizes the difference in propagation speed between the shear wave noise and the re-flected signal to separate shear wave noise and effective wave as much as possible in the r-q domain.Secondly,the shear wave noise is extracted by removing the reflected signal component in the P-component from the z-component data containing the shear wave noise through the high flexibility of the unsteady adaptive subtraction algorithm.Finally,the extracted shear wave noise is transformed back to the spatio-temporal domain and re-moved from the original z-component data.The reflected signal in the recorded data is preserved as much as possible while realizing the elimination of noise.Processing results of actual data demonstrate that this method can effectively suppress the shear wave noise in OBN data and improve the signal-to-noise ratio of the seismic data.
万方数据
维普
