脉冲编码震源的匹配冲击技术
|
摘要
常规Vibroseis可控震源Chirp扫描的地震响应存在明显的旁瓣效应,二元m-序列伪随机扫描的解码地震剖面中存在严重的相关噪声,而基于伪随机编码的匹配扫描方法可有效压制解码地震剖面中的相关噪声,提高了地震记录的信噪比.为了将匹配伪随机编码方法应用到冲击式震源中,提出了基于脉冲编码震源的匹配冲击技术.以匹配扫描方法为理论基础给出了匹配冲击信号的编码与解码过程,以有限元差分法对匹配冲击技术和常规线性扫描冲击技术进行了地震数值模拟.结果表明,匹配冲击的综合解码地震剖面中,不存在线性扫描冲击解码地震剖面中能量较强的相关噪声干扰,剖面具有很高的信噪比和分辨率.地震波激发采集对比实验验证了匹配冲击技术在压制相关噪声及远偏移距地震道随机噪声方面相比线性扫描冲击技术所具有的优势.
Seismic response of conventional Chirp sweeping for Vibroseis has obvious side-lobe effect and the decoded seismic section of binary m-sequence pseudorandom sweeping has serious correlation noises,while the matched sweeping method based on pseudorandom coding can suppress the correlation noises in the seismic section effectively and improve the SNR of seismic records.In order to apply the matched pseudorandom coding method to impact seismic sources,matched impact seismic technique for pulse-coded seismic sources was developed.The coding and decoding processes for matched impact signals were given with matched sweeping method as the rationale.Simultaneously,seismic numerical simulation for matched impact seismic technique and the conventional linear swept impact technique were conducted using finite difference method.The results show that the decoded seismic section for matched impact method has very high SNR and seismic resolution without the correlation noises in comparison with the linear swept impact method.The seismic excitation and acquisition experiments verify the superiority of matched impact seismic technique in suppressing the correlation noises and the random noises of large-offset seismic traces compared with the linear swept impact technique.
Seismic response of conventional Chirp sweeping for Vibroseis has obvious side-lobe effect and the decoded seismic section of binary m-sequence pseudorandom sweeping has serious correlation noises,while the matched sweeping method based on pseudorandom coding can suppress the correlation noises in the seismic section effectively and improve the SNR of seismic records.In order to apply the matched pseudorandom coding method to impact seismic sources,matched impact seismic technique for pulse-coded seismic sources was developed.The coding and decoding processes for matched impact signals were given with matched sweeping method as the rationale.Simultaneously,seismic numerical simulation for matched impact seismic technique and the conventional linear swept impact technique were conducted using finite difference method.The results show that the decoded seismic section for matched impact method has very high SNR and seismic resolution without the correlation noises in comparison with the linear swept impact method.The seismic excitation and acquisition experiments verify the superiority of matched impact seismic technique in suppressing the correlation noises and the random noises of large-offset seismic traces compared with the linear swept impact technique.
引文
[1]唐杰,王宝善,葛洪魁等.小当量激发的远距离信号检测研究.地球物理学报,2008,51(6):1810-1818.Tang J,Wang B S,Ge H K,et al.Study on weak signaldetection of small shot in regional scale deep exploration.Chinese J.Geophys.(in Chinese),2008,51(6):1810-1818.
[2]李文军,李丽,陈棋福.用震源扫描算法(SSA)研究列车源的运动.地球物理学报,2008,51(4):1146-1151.Li W J,Li L,Chen Q F.Research on the movement ofvibration source of train by means of SSA.Chinese J.Geophys.(in Chinese),2008,51(4):1146-1151.
[3]陶知非,赵永林,马磊.低频地震勘探与低频可控震源.物探装备,2011,21(2):71-76.Tao Z F,Zhao Y L,Ma L.Low frequency seismic and lowfrequency vibrator.Equipment for Geophysical Prospecting(in Chinese),2011,21(2):71-76.
[4]赵明辉,丘学林,夏少红等.大容量气枪震源及其波形特征.地球物理学报,2008,51(2):558-565.Zhao M H,Qiu X L,Xia S H,et al.Large volume air-gunsources and its seismic waveform characters.Chinese J.Geophys.(in Chinese),2008,51(2):558-565.
[5]林建民,王宝善,葛洪魁等.大容量气枪震源子波激发特性分析.地球物理学报,2010,53(2):342-349.Lin J M,Wang B S,Ge H K,et al.Characters of largevolume air-gun source excitation.Chinese J.Geophys.(inChinese),2010,53(2):342-349.
[6]Goupillaud P L.Signal Design in the"Vibroseis"Technique.Geophysics,1976,41(6):1291-1304.
[7]Chapman W L,Brown G L,Fair D W.The Vibroseissystem:A high-frequency tool.Geophysics,1981,46(12):1657-1666.
[8]王忠仁,樊丹丹,高健等.基于三元伪随机编码的可控震源信号设计方法.石油地球物理勘探,2009,44(5):534-536.Wang Z R,Fan D D,Gao J,et al.Vibroseis signal designingbased on ternary pseudo-random coding technology.OilGeophysical Prospecting(in Chinese),2009,44(5):534-536.
[9]王忠仁,高健,林君.可控震源匹配扫描方法研究.地球物理学报,2010,53(11):2754-2759.Wang Z R,Gao J,Lin J.Matched sweep method for seismicvibrators.Chinese J.Geophys.(in Chinese),2010,53(11):2754-2759.
[10]Ei-Aal A.Harmonic by harmonic removal technique forimproving vibroseis data quality.Geophysical Prospecting,2011,59(2):279-294.
[11]曹务祥,闫智慧,邹小燕等.利用可控震源的力信号压制谐波干扰.石油物探,2011,50(1):89-92.Cao W X,Yan Z H,Zou X Y,et al.Harmonic interferencesuppressing by force signal of vibroseis.Geophysical Prospectingfor Petroleum(in Chinese),2011,50(1):89-92.
[12]Wei Z H,Hall M A.Analyses of vibrator and geophonebehavior on hard and soft ground.The Leading Edge,2011,30(2):132-137.
[13]Park C B,Miller R D,Steeples D W,et al.Swept impactseismic technique(SIST).Geophysics,1996,61(6):1789-1803.
[14]Cosma C,Enescu N.Characterization of fractured rock in thevicinity of tunnels by the swept impact seismic technique.International Journal of Rock Mechanics and Mining Sciences,2001,38(6):815-821.
[15]王忠仁,高健,孙锋.脉冲编码可控震源信号设计.地球物理学进展,2008,23(6):1931-1935.Wang Z R,Gao J,Sun F.Signal design for controllableseismic source by pulse coding.Progress in Geophysics(inChinese),2008,23(6):1931-1935.
[16]Barbier M G,Bondon P,Mellinger R,et al.Mini-SOSIE forland seismology.Geophysical Prospecting,1976,24(3):518-527.
[17]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):864-870.Ge H K,Lin J M,Wang B S,et al.A field experiment studyof improving the seismic detectability with coded source.Chinese J.Geophys.(in Chinese),2006,49(3):864-870.
[18]常旭,李林新,刘伊克等.北京断陷黄庄-高丽营断层伪随机可控震源地震剖面.地球物理学报,2008,51(5):1503-1510.Chang X,Li L X,Liu Y K,et al.Seismic profile ofHuangzhuang-Gaoliying fault in Beijing by Mini-sosie method.Chinese J.Geophys.(in Chinese),2008,51(5):1503-1510.
[2]李文军,李丽,陈棋福.用震源扫描算法(SSA)研究列车源的运动.地球物理学报,2008,51(4):1146-1151.Li W J,Li L,Chen Q F.Research on the movement ofvibration source of train by means of SSA.Chinese J.Geophys.(in Chinese),2008,51(4):1146-1151.
[3]陶知非,赵永林,马磊.低频地震勘探与低频可控震源.物探装备,2011,21(2):71-76.Tao Z F,Zhao Y L,Ma L.Low frequency seismic and lowfrequency vibrator.Equipment for Geophysical Prospecting(in Chinese),2011,21(2):71-76.
[4]赵明辉,丘学林,夏少红等.大容量气枪震源及其波形特征.地球物理学报,2008,51(2):558-565.Zhao M H,Qiu X L,Xia S H,et al.Large volume air-gunsources and its seismic waveform characters.Chinese J.Geophys.(in Chinese),2008,51(2):558-565.
[5]林建民,王宝善,葛洪魁等.大容量气枪震源子波激发特性分析.地球物理学报,2010,53(2):342-349.Lin J M,Wang B S,Ge H K,et al.Characters of largevolume air-gun source excitation.Chinese J.Geophys.(inChinese),2010,53(2):342-349.
[6]Goupillaud P L.Signal Design in the"Vibroseis"Technique.Geophysics,1976,41(6):1291-1304.
[7]Chapman W L,Brown G L,Fair D W.The Vibroseissystem:A high-frequency tool.Geophysics,1981,46(12):1657-1666.
[8]王忠仁,樊丹丹,高健等.基于三元伪随机编码的可控震源信号设计方法.石油地球物理勘探,2009,44(5):534-536.Wang Z R,Fan D D,Gao J,et al.Vibroseis signal designingbased on ternary pseudo-random coding technology.OilGeophysical Prospecting(in Chinese),2009,44(5):534-536.
[9]王忠仁,高健,林君.可控震源匹配扫描方法研究.地球物理学报,2010,53(11):2754-2759.Wang Z R,Gao J,Lin J.Matched sweep method for seismicvibrators.Chinese J.Geophys.(in Chinese),2010,53(11):2754-2759.
[10]Ei-Aal A.Harmonic by harmonic removal technique forimproving vibroseis data quality.Geophysical Prospecting,2011,59(2):279-294.
[11]曹务祥,闫智慧,邹小燕等.利用可控震源的力信号压制谐波干扰.石油物探,2011,50(1):89-92.Cao W X,Yan Z H,Zou X Y,et al.Harmonic interferencesuppressing by force signal of vibroseis.Geophysical Prospectingfor Petroleum(in Chinese),2011,50(1):89-92.
[12]Wei Z H,Hall M A.Analyses of vibrator and geophonebehavior on hard and soft ground.The Leading Edge,2011,30(2):132-137.
[13]Park C B,Miller R D,Steeples D W,et al.Swept impactseismic technique(SIST).Geophysics,1996,61(6):1789-1803.
[14]Cosma C,Enescu N.Characterization of fractured rock in thevicinity of tunnels by the swept impact seismic technique.International Journal of Rock Mechanics and Mining Sciences,2001,38(6):815-821.
[15]王忠仁,高健,孙锋.脉冲编码可控震源信号设计.地球物理学进展,2008,23(6):1931-1935.Wang Z R,Gao J,Sun F.Signal design for controllableseismic source by pulse coding.Progress in Geophysics(inChinese),2008,23(6):1931-1935.
[16]Barbier M G,Bondon P,Mellinger R,et al.Mini-SOSIE forland seismology.Geophysical Prospecting,1976,24(3):518-527.
[17]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):864-870.Ge H K,Lin J M,Wang B S,et al.A field experiment studyof improving the seismic detectability with coded source.Chinese J.Geophys.(in Chinese),2006,49(3):864-870.
[18]常旭,李林新,刘伊克等.北京断陷黄庄-高丽营断层伪随机可控震源地震剖面.地球物理学报,2008,51(5):1503-1510.Chang X,Li L X,Liu Y K,et al.Seismic profile ofHuangzhuang-Gaoliying fault in Beijing by Mini-sosie method.Chinese J.Geophys.(in Chinese),2008,51(5):1503-1510.
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