基于互信息量的地震信号检测和初至提取方法
|
摘要
本文将现代信息科学中的重要基础理论———信息论引入到地震信号的分析和处理中,提出了一种利用互信息量检测地震信号并进行初至提取的方法,给出了该方法的基本原理和具体算法.计算结果表明,互信息量随滑动窗口移动的变化情况可以明确标示出待测地震信号的存在,通过提取互信息量的突变点或峰值点,能够有效拾取地震波的初至时刻.这种方法还可以特别针对非传统的地震信号,如连续随机信号、随机脉冲序列等进行处理.在这些信号条件下,往往信噪比很低,波形随传播距离发生较大变化,传统的信号检测方法效果不佳,而这种以随机信号检测为基础的互信息量探测方法具有很好的性能,很有发展前景.
In this paper the fundamental theory of information science-Information Theory is introduced to the analysis and processing of seismic signals. Based on mutual information, a novel seismic signals detection and first arrival pickup method is proposed with the principle and detail algorithm. The computation results on real seismic data show that mutual information in the sliding observation window can indicate the existence of the seismic signals to be detected. Through the pickup of the rising-break or the peak point of mutual information, the arrival time can also be effectively estimated. Especially, the presented method can be used in the processing of the non-classical seismic signals such as continuous stochastic signals and random impulse sequences. When analyzing these kinds of signals, the signal noise ratio is usually very low and seismic waves will change apparently with the transmit distance. So it is difficult to analyze these signals by classical detection methods, but the proposed method can provide some useful results in these situations.
In this paper the fundamental theory of information science-Information Theory is introduced to the analysis and processing of seismic signals. Based on mutual information, a novel seismic signals detection and first arrival pickup method is proposed with the principle and detail algorithm. The computation results on real seismic data show that mutual information in the sliding observation window can indicate the existence of the seismic signals to be detected. Through the pickup of the rising-break or the peak point of mutual information, the arrival time can also be effectively estimated. Especially, the presented method can be used in the processing of the non-classical seismic signals such as continuous stochastic signals and random impulse sequences. When analyzing these kinds of signals, the signal noise ratio is usually very low and seismic waves will change apparently with the transmit distance. So it is difficult to analyze these signals by classical detection methods, but the proposed method can provide some useful results in these situations.
引文
[1]常旭,刘伊克.Hausdorff分数维识别地震道初至走时.地球物理学报,1998,41(6):826～832Chang X,Liu Y K.Distinguishing seismic first break by means of Hausdorff fractal dimension.Chinese J.Geophys.(in Chinese),1998,41(6):826～832
[2]Joseph B,Molyneux and Douglas R.Schmitt.First-break timing:arrival onset times by direct correlation.Geophysics,1999,64(5):1492～1501
[3]Boschetti F,Dentith D M,List D R.Afractal-based algorithmfor detectingfirst arrivals on seismic traces.Geophysics,1996,61(4):1095～1102
[4]常旭,刘伊克.地震记录的广义分维及其应用.地球物理学报,2002,45(6):839～846Chang X,Liu Y K.The generalized fractal dimension of seismic records and its applications.Chinese J.Geophys.(in Chinese),2002,45(6):839～846
[5]Peraldi R,Clement A.Digital processing of refraction data-study of first arrivals.Geophys.Prosp.,1972,20:529～548
[6]Gelchinsky B,Shtivelman V.Automatic picking of first arrivals and parameterization of traveltime curves.Geophys.Prosp.,1983,31:915～928
[7]葛洪魁,林建民,王宝善等.编码震源提高地震探测能力的野外实验研究.地球物理学报,2006,49(3):864～870Ge HK,Lin J M,Wang B S,et al.Afield experiment study of improving the seismic detectability with coded source.Chinese J.Geophys.(in Chinese),2006,49(3):864～870
[8]Shannon C E.A mathematical theory of communication.The Bell SystemTechnical Journal,1948,27:379～423(Part I),625～656(PartⅡ)
[9]姜丹,钱玉美.信息论与编码.合肥:中国科学技术大学出版社,1992.14～149Jiang D,Qian Y M.Information Theory and Coding(in Chinese).Hefei:University of Science and Technology of China Press,1992.14～149
[10]Hegger R,Kantz H,Schreiber T.Practical implementation of nonlinear time series methods:the TISEAN package.CHAOS,1999,9:413～435
[2]Joseph B,Molyneux and Douglas R.Schmitt.First-break timing:arrival onset times by direct correlation.Geophysics,1999,64(5):1492～1501
[3]Boschetti F,Dentith D M,List D R.Afractal-based algorithmfor detectingfirst arrivals on seismic traces.Geophysics,1996,61(4):1095～1102
[4]常旭,刘伊克.地震记录的广义分维及其应用.地球物理学报,2002,45(6):839～846Chang X,Liu Y K.The generalized fractal dimension of seismic records and its applications.Chinese J.Geophys.(in Chinese),2002,45(6):839～846
[5]Peraldi R,Clement A.Digital processing of refraction data-study of first arrivals.Geophys.Prosp.,1972,20:529～548
[6]Gelchinsky B,Shtivelman V.Automatic picking of first arrivals and parameterization of traveltime curves.Geophys.Prosp.,1983,31:915～928
[7]葛洪魁,林建民,王宝善等.编码震源提高地震探测能力的野外实验研究.地球物理学报,2006,49(3):864～870Ge HK,Lin J M,Wang B S,et al.Afield experiment study of improving the seismic detectability with coded source.Chinese J.Geophys.(in Chinese),2006,49(3):864～870
[8]Shannon C E.A mathematical theory of communication.The Bell SystemTechnical Journal,1948,27:379～423(Part I),625～656(PartⅡ)
[9]姜丹,钱玉美.信息论与编码.合肥:中国科学技术大学出版社,1992.14～149Jiang D,Qian Y M.Information Theory and Coding(in Chinese).Hefei:University of Science and Technology of China Press,1992.14～149
[10]Hegger R,Kantz H,Schreiber T.Practical implementation of nonlinear time series methods:the TISEAN package.CHAOS,1999,9:413～435
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