用S变换做精细时变滤波
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摘要
在地震记录中如何精确地去除干扰波而又不损失有效信号,目前是地震勘探行业内广泛研究的问题,各种新型算法被应用于这个领域,这些算法各有优劣。S变换是一种新出现的数学变换方法,已被广泛应用于各种信号的时频分析,但还未用于去除地震记录中的噪音方面。文章对S变换的应用作了推广,给出了用S变换定点清除地震记录中噪音的方法。针对地震资料的特点提出了应用S变换消除干扰的具体计算方法。首先将地震资料用S变换方法变换到时间—频率域;然后利用地震信号与噪音在时间—频率域的差异,精确滤除信号中所含噪音;最后将去噪后的地震数据利用S反变换变换到时间域,以获得所需要的有效信号。大量的理论模型计算表明,S变换确为一种定点去除不同时段、不同频率噪音的有效方法,几个地区的实际地震资料试算也表明了该方法的有效性。
Accurate elimination of interference waves without losing effective signals in seismic records is a common concern of seismic exploration. Many new algorithms with their own superior and inferior have been applied in this field. S-transformation is a new mathematical transformation method, which has been widely used in time-frequency analyses of various signals but has not been applied to elimination of noise in seismic records. Application of S-transformation is expanded to the fixed point elimination of noise in seismic records. The specific algorithms of noise elimination through S-transformation are presented in view of the characteristics of seismic data. Seismic data are first transformed into time-frequency domain by using the S-transformation methods. Then the noise in signals is accurately eliminated by making use of the difference of seismic signal and noise in time-frequency domain. Finally, the seismic data after noise elimination are transformed into time domain again by using S-inverse transformation to achieve the effective signals needed. Based on large amount of theoretical model calculations, it is believed that S-transformation is really an effective method of the fixed point elimination of noises at different time intervals and with different frequencies. Trial calculation of real seismic data in several areas also verifies its effectiveness.
引文
[1]STOCKWELL R G,MANSINHA L,LOWE R P.Locali-zation of the complex spectrum:the S transform[J].IEEE Tran.On Signal Processing,1996,17:998-1001.
    [2]高静怀,汪文秉,朱光明,等.地震资料处理中小波函数的选取[J].地球物理学报,1996,39(3):392-400.
    [3]俞寿朋.高分辨率地震勘探[M].北京:石油工业出版社,1993.
    [4]李学义.四川盆地碳酸盐岩地区地震勘探技术难点及对策探讨[J].天然气工业,2000,20(2).
    [5]伍志明,李亚林,贺振华,等.高陡复杂构造的地震成像技术进展[J].天然气工业,2004,24(2).
    [6]徐峰,马在田.库车坳陷盐下含油气构造地震勘探的关键技术[J].天然气工业,2003,23(3).

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