Technical Research Based On Multi-domain Noise Elimination

The ratio of signal and noise is the basis in seismic data processin.High resolution and high fideliy couldn't realize without higher S/N ratio. And The processing technique and method is useless without that. especially noise elimination after stack. With the development of oil exploration, the problems to be solved turn esoteric, and geological conditions from the surface to underground is more and more complex. So seismic data processing have to focus on pre-stack. The kind of noise is variety. There are targeted and adapted to every method. Usually, different methods of noiseattenuation have different pertinence and adaptability. Without a method is valid to all kinds of noise. Therefore, the noise elimination should be processed in multi-domain.In the paper, firstly, we have discussed the cause, the distributing, the degree of complex and the type of kinds of noise and especially, have discussed the characteristic of these noise in detail. Secondly, we have analyzed the peculiarity difference between noise and signal in multi-domain and amplify their difference in a domain. Then, we can design an arithmetic operator of noise suppression and realize the separation of signal and noise. And these methods of noise suppression have been demonstrated according to the theory of noise generation and characteristic. In this paper improves the menthod of surface wave suppression using 2-D wavelet transform. Compared with conventional FK filtering, the advantages of this method is to maximize maintain effective wave. In addition, the advantages and disadvantages of the KL transform, f-x forecast de-noising, wavelet threshold de-noising was compared.We have chosen the representative sismic data which include tpical noise from different area and processed them by using noise suppression technique in multi-domain and their combination.The effect of processing is obvioushly. And we reached the destination of improving S/N ratio.This indicate that the method is feasible and effectual. Finally, we have analyzed the whole effect to the technique of multi-domain noise elimination and obtained some understanding.