Multiple Attenuation By Radon Transform Method Incorporating With Prediction Based On Wave Equation

At present,multiples are usually treated as coherent noises which need to be suppressed in seismic data processing area. The commonly used methods include multiple method based on wave-equation and multiple suppression method based on filtering, The former is data driven which does not need prior information, and it can cope with complex underground structure but it has high calculation cost and request for whole wave-field data. While the latter has high calculation rate, and would fail when the assumption about different moveouts between primary and multiples are not met, it can not deal with complex structure media, and the attenuation results are usually not satisfied. This paper proposes to combine wave-equation-based prediction method with parabolic Radon transform.. First use SRME method to obtain multiple prediction model, use it as references, design Butterworh filter in parabolic domain, obtain the primary, after inverse transform, by means of original data, obtain the final multiple attenuation result. GPU/CPU collaborative parallel computation technique is introduced into the prediction algorithm to improve calculation efficiency.Traditional parabolic Radon transform fails to calculate seismic profile when multiples are generated from complex underground media or simultaneous shots geometry. So it is necessary to introduce apex shifted Radon transform in space frequency domain, this method can deal with events which the parabolas are located in different offset position, make the energy focus in the correct position. In addition, to decrease the artifact, and also to improve the precision of imaging in the transform domain, curvature parameter is substituted by time-delay value Γ during the integral. The artifacts in the time-delay Radon domain is decided by the trace number in the input CMP or shot records, not the spatial interval along offset direction in the traditional Radon transform algorithm. The pre-condition operator is used to acquire better multiple suppression result.Test results show that, the propose method improves calculation precision and computation efficiency, suppress the artifacts in Radon domain effectively, make best use of multiple prediction method based on wave theory and parabolic Radon transform. It can deal with seismic data from complex structure successfully, it can be applied on multiple attenuation of marine data well, and has good development prospects.