【作者】 张成玉；

【导师】 李振春；

【作者基本信息】 中国石油大学 ， 地球探测与信息技术， 2009， 硕士

【摘要】 在地震资料处理中,地震资料的高信噪比是基础。没有一定的信噪比,高分辨率和高保真就不可能实现;没有一定的信噪比做保障,再先进的处理技术和方法都是枉然。随着石油勘探的不断发展,地震资料所要解决的问题也越来越深入,地质条件从地表到地下都越来越复杂,地震资料的处理重点也转向叠前。噪声种类繁多,不同的去噪方法通常都有其不同的针对性、适应性,没有一种方法对各种干扰都是有效的,因此消除各种干扰应采用多域内多种方法联合压制噪音。文中对各种噪音产生的原因、干扰程度、发育程度及其类型、特点等,作了详尽的分析。针对地震资料中不同类型的噪音,具体分析它们在不同域中的特征与有效波之间的差异,使它们之间的差异在某一域内最大化,然后设计出合适的去噪算子进行信噪分离。文中依据这个原理,论证了一些去噪方法。改进了二维小波变换压制面波方法,较之常规的FK滤波能最大限度地保护了有效波;另外比较了KL变换, f ? x预测预测去噪,小波阈值去噪等随机噪声压制方法的优缺点。选取具有典型噪音类型地区的地震资料运用多域多种去噪方法优化组合方法进行去噪处理,处理效果明显,提高了资料的信噪比。验证和说明了多域去噪的可行性和有效性。最后,对多域去噪技术进行了效果分析,并取得了一些认识。更多还原

【Abstract】 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.更多还原