地震数据处理中关于地震子波相位特性的探讨
|
摘要
本文就实际地震数据处理中常用的地震子波最小相位化、预滤波、叠前反褶积和叠后地震子波零相位化等四个处理模块对地震子波相位特性的影响进行了探讨。当地震记录是由可控震源激发得到时,其地震子波是可控震源扫描信号的自相关,呈零相位子波特性,此时需将零相位子波转化为最小相位子波,为后续的反褶积处理做准备;当地震记录是由炸药震源激发得到时,其地震子波一般被认为是最小相位子波,在对此地震数据进行叠前反褶积处理之前首先使用一个高通滤波器对其进行预滤波处理(这个滤波器必须是最小相位的,因为最小相位地震子波只有经过最小相位滤波器滤波后才是最小相位的),然后进行叠前反褶积处理(主要包括脉冲反褶积、地表一致性反褶积等,该处理过程要求输入地震数据的地震子波是最小相位的),经过这些反褶积处理后的地震数据的子波也认为是最小相位的;因零相位子波的地震剖面分辨率最高,所以最后还需再对叠后数据的最小相位子波进行零相位化处理。以上认识已在巴基斯坦E工区二维地震资料的处理中得到验证。
The paper carried out the discussion on influence of four common-used processing modules (seismic wavelet phase minimization, pre-filtering, prestack deconvolution and poststack seismic wavelet zero-phasing) on phase character of seismic wavelet. The seismic wavelet is autocorrelation of sweeping signal of vibroseis when the seismic record is acquired by vibroseis shooting, which is characteristic of zero-phase wavelet and should need transform the zero-phase wavelet into minimum-phase wavelet, preparing subsequent deconvolution processing; the seismic wavelet is generally considered as minimum-phase wavelet when the seismic records is acquired by dynamite shooting, firstly, before prestack deconvolution processing of seismic data, it should use high-pass filter for pre-filtering processing (the filter should be minimum-phase, because the minimum-phase seismic wavelet is the minimum phase only after filtering of minimum-phase filter), then, the prestack deconvolution processing is carried out (mainly including pulse deconvolution, surface-consistent deconvolution, which demands input seismic wavelet of seismic data to be minimum phase), the wavelet of deconvolution-processed seismic wavelet is also considered as minimum phase; because the seismic section with zero-phase wavelet is characteristic of high resolution, the zero-phase processing of minimum-phase wavelet on poststack sections should finally be carried out again. Above knowledge has been proved by the 2D seismic data processing in E area of Pakistan.
The paper carried out the discussion on influence of four common-used processing modules (seismic wavelet phase minimization, pre-filtering, prestack deconvolution and poststack seismic wavelet zero-phasing) on phase character of seismic wavelet. The seismic wavelet is autocorrelation of sweeping signal of vibroseis when the seismic record is acquired by vibroseis shooting, which is characteristic of zero-phase wavelet and should need transform the zero-phase wavelet into minimum-phase wavelet, preparing subsequent deconvolution processing; the seismic wavelet is generally considered as minimum-phase wavelet when the seismic records is acquired by dynamite shooting, firstly, before prestack deconvolution processing of seismic data, it should use high-pass filter for pre-filtering processing (the filter should be minimum-phase, because the minimum-phase seismic wavelet is the minimum phase only after filtering of minimum-phase filter), then, the prestack deconvolution processing is carried out (mainly including pulse deconvolution, surface-consistent deconvolution, which demands input seismic wavelet of seismic data to be minimum phase), the wavelet of deconvolution-processed seismic wavelet is also considered as minimum phase; because the seismic section with zero-phase wavelet is characteristic of high resolution, the zero-phase processing of minimum-phase wavelet on poststack sections should finally be carried out again. Above knowledge has been proved by the 2D seismic data processing in E area of Pakistan.
引文
[1]Yil maz O.Seismic Data Analysis:Processing,Inver-sion and Interpretation of Seismic Data,2001
[2]周兴元.常相位校正.石油地球物理勘探,1989,24(2):119~129
[3]郭向宇,董敏煜.混合相位子波的相位估算及校正.石油地球物理勘探,1998,33(2):214~221
[4]李庆忠.走向精确的勘探道路.北京:石油工业出版社,1993
[5]俞寿朋.高分辨地震勘探.北京:石油工业出版社,1993
[6]牟永光.地震勘探资料数据处理方法.北京:石油工业出版社,1981
[2]周兴元.常相位校正.石油地球物理勘探,1989,24(2):119~129
[3]郭向宇,董敏煜.混合相位子波的相位估算及校正.石油地球物理勘探,1998,33(2):214~221
[4]李庆忠.走向精确的勘探道路.北京:石油工业出版社,1993
[5]俞寿朋.高分辨地震勘探.北京:石油工业出版社,1993
[6]牟永光.地震勘探资料数据处理方法.北京:石油工业出版社,1981
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心