The Research Of Multiple Attenuation Based On Co-Core Trace Transform

The seismic prospecting is one of the important methods in physical geography,it is one of the most effective way to find out the underground geologic structure. Inseismic exploration, it is the multiple wave which is the common coherentinterference wave, that troubles the geological researchers all the time. How to solvethe problem of multiple attenuation is very important in seismic exploration,especially in oil and gas exploration, it is the multiple wave that causes the SNR ofseismic data to reduce greatly, interferes the recognition of the effective waves, alsoit will seriously influence the seismic interpretation and follow-up work of seismicdata prospecting. So the researchers at home and abroad after a long time strugglingand unremitting efforts finally propose many methods to solve the problems ofmultiple attenuation. All the methods can be generally divided into two catagories:the method of filtering and the method that based on the wave equation.This paper first introduces the causes of the multiple wave, it features and themethods of multiple identification, the technology of multiple attenuation and itscharacteristics are detailed introduced here. In all the filtering methods, Radontransform is widely used in multiple attenuation, in Radon transform the focal pointof effective wave and multiple wave is different, and they present different form inthe transform domain, we can separate the data which we don’t need in Radondomain, and after inverse transform we will get the data we want. But in traditionalRadon transform, it has the defect,“tail” phenomenon. This paper based on theRadon transform, proposes its general form Trace transform also having the abilityin multiple attenuation. The Trace transform proposed, a generalization of the Radon,which will not be limited only in integral form in dealing with problems, is widelyused in invariant feature construction, image registration, change detection andrecord identification. The paper gives the detailed introduction of the Tracetransform, in order to gather more energy of the effective wave, here we introducethe theory named Co-Core Trace Transform to attenuate multiple. This method firsttransform the data needed to deal with into Trace transform domain, in the domainthe energy of the effective wave is significantly enlarged, which make the differencemore greater between the effective wave and the multiple wave. By thresholding, we can see the good recovery of effective wave, and the multiple wave is attenuated.The algorithm and derivation of equation are introduced in the paper, using thismethod to recover the effective wave is feasible. Through making use of the methodin180channels seismic date, we can see the good recovery of effective wave. TheAmplitude fading is little contrasted the single channel. Add some random noise inmultiple wave record, we do the experiment again and find after transform the theeffective wave can be recovered very well, so the method used here not only canattenuate the multiple wave but also has ability in random attenuation. We also usethe method to deal with the real seismic signal, and get the conclusion that theCo-Core Trace transform do have a good performance in multiple attenuation.