利用背景噪声数据提取地震台站间面波的可靠性分析——以中国大陆中东部地区的宽频带台站为例
|
摘要
利用中国大陆中东部地区以国家台网为主的100个分布均匀的宽频带地震台记录到的21个月的连续波形数据,经过单台数据处理和互相关叠加计算后,由时频分析法提取了研究区各台站对间瑞雷波的格林函数.为了检验经验格林函数的可靠性和稳定性,对沿部分路径的经验格林函数和频散曲线进行了质量评估.检测结果表明,自21个月叠加的台站对间背景噪声中提取的经验格林函数与实际的地震面波一致,提取的格林函数可靠.此外,统计了使用从3—21个月不同长度数据叠加后,经验格林函数信噪比大于10的频散曲线数目.结果表明,至少要使用12个月的数据才能提取到信噪比足够大,数目足够多,可用于反演面波速度结构的经验格林函数;12个月的叠加时长,可以保证30s以下周期的频散曲线在时间上稳定.
We retrieved Rayleigh wave Green functions between all possible station pairs after pre-processing, cross-correlation and stacking the data, which are 21 months' continuous ambient seismic noise recorded by 100 evenly distributed broadband seismic stations mainly in the National Seismic Network in central and eastern Chinese mainland. The quality of the empirical Green functions (EGFs) and the dispersion curves along selected paths were estimated to measure the reliability and stability of the EGFs. Our results display that the EGFs are correlated with the earthquake signals, suggesting the reliability of the EGFs. In addition, we counted the number of dispersion measurements with SNR>10 retrieved from the time-series of different lengths (3—21 months). The result shows that, to obtain enough reliable EGFs for velocity tomography, at least 12 months' data should be used and 12 months’ data can make sure that dispersion curves under 30 s are temporally stable.
We retrieved Rayleigh wave Green functions between all possible station pairs after pre-processing, cross-correlation and stacking the data, which are 21 months' continuous ambient seismic noise recorded by 100 evenly distributed broadband seismic stations mainly in the National Seismic Network in central and eastern Chinese mainland. The quality of the empirical Green functions (EGFs) and the dispersion curves along selected paths were estimated to measure the reliability and stability of the EGFs. Our results display that the EGFs are correlated with the earthquake signals, suggesting the reliability of the EGFs. In addition, we counted the number of dispersion measurements with SNR>10 retrieved from the time-series of different lengths (3—21 months). The result shows that, to obtain enough reliable EGFs for velocity tomography, at least 12 months' data should be used and 12 months’ data can make sure that dispersion curves under 30 s are temporally stable.
引文
李昱,姚华健,刘启元,陈九辉,van der Hilst R D,李顺成,黄慧,郭飚,王峻,齐少华.2010.川西地区台阵环境噪声瑞利波相速度层析成像[J].地球物理学报,53(4):842--852.
刘志坤,黄金莉.2010.利用背景噪声互相关研究汶川地震震源区地震波速度变化[J].地球物理学报,53(4):853--863.
赵盼盼.2011.汶川地震区地壳速度相对变化的地震环境噪声自相关研究[D].北京:中国地震局地质研究所:1--50.
郑秀芬,欧阳飚,张东宁,姚志祥,梁建宏,郑洁.2009.“国家数字测震台网数据备份中心”技术系统建设及其对汶川大地震研究的数据支撑[J].地球物理学报,52(5):1412--1417.
郑现,赵翠萍,周连庆,郑斯华.2012.中国大陆中东部地区基于背景噪声的瑞利波层析成像[J].地球物理学报,55(6):1919--1928.
Bensen G B,Ritzwoller M H,Barmin M P,Levshin A L,Lin F,Moschetti M P,Shapiro N M,Yang Y.2007.Process-ing seismic ambient noise data to obtain reliable broad-band surface wave dispersion measurements[J].Geophys JInt,169(3):1239--1260.
Bensen G B,Ritzwoller M H,Shapiro N M.2008.Broadband ambient noise surface wave tomography across the UnitedStates[J].J Geophys Res,113(B5306):1--21.
Brenguier F N,Shapiro N M,Campillo M,Ferrazzini V,Duputel Z,Coutant O,Nercessian A.2008a.Towards foresca-sting volcanic eruptions using seismic noise[J].Nat Geosci,1(2):126--130.
Brenguier F N,Campillo M,Hadziioannou C,Shapiro N M,Nadeau R M,Larose E.2008b.Postseismic relaxationalong the San Andreas Fault at Parkfield from continuous seismological observations[J].Science,321(5895):1478.
Campillo M,Paul A.2003.Long-range correlations in the diffuse seismic coda[J].Science,299(5606):547--549.
Chen J H,Froment B,Liu Q Y,Campillo M.2010.Distribution of seismic wave speed changes associated with the12May2008MW7.9Wenchuan earthquake[J].Geophys Res Lett,37(18):L18302,doi:10.1029/2010GL044582.
Fang L H,Wu J P,Ding Z F,Panza G F.2010.High resolution Rayleigh wave group velocity tomography in North Chi-na from ambient seismic noise[J].Geophys J Int,181(2):1171--1182.
Kang T S,Shin J S.2006.Surface-wave tomography from ambient seismic noise of accelerograph networks in southernKorea[J].Geophys Res Lett,33(L17303):1--5.
Levshin A L,Ritzwoller M H.2001.Automated detection,extraction,and measurement of regional surface waves[J].Pure Appl Geophys,158(8):1531--1545.
Li H,Su W,Wang C,Huang Z.2009.Ambient noise Rayleigh wave tomography in western Sichuan and eastern Tibet[J].Earth Planet Sci Lett,282(1--4):201--211.
Lin F,Ritzwoller M H,Townend J,Bannister S,Savage M K.2007.Ambient noise Rayleigh wave tomography of NewZealand[J].Geophys J Int,170(2):649--666.
Lin F,Moschetti M P,Ritzwoller M H.2008.Surface wave tomography of the western United States from ambient seis-mic noise:Rayleigh and Love wave phase velocity maps[J].Geophys J Int,173(1):281--298.
Lobkis O I,Weave R L.2001.On the emergence of the Green’s function in the correlations of a diffuse field[J].JAcoust Soc Amer,110(6):3011--3017.
Nishida K,Montagner J P,Hitoshi K.2009.Global surface wave tomography using seismic hum[J].Science,326(5949):112.
Shapiro N M,Ritzwoller M H.2002.Monte-Carlo inversion for a global shear-velocity model of the crust and upper man-tle[J].Geophys J Int,151(1):88--105.
Shapiro N M,Campillo M.2004.Emergence of broadband Rayleigh waves from correlations of the ambient seismic noise[J].Geophys Res Lett,31(7):1--5.
Shapiro N M,Campillo M,Stehly L,Ritzwoller M H.2005.High-resolution surface-wave tomography from ambientseismic noise[J].Science,305(5681):233--236.
Sun X L,Song X D,Zheng S H,Yang Y J,Ritzwoller M H.2010.Three dimensional shear wave velocity structure ofthe crust and upper mantle beneath China from ambient noise surface wave tomography[J].Earthq Sci,23(5):449--463.
Weaver R L,Lobkis O I.2001.Ultrasonics without a source Thermal fluctuation correlations at MHz frequencies[J].Phys Rev Lett,87(13):134301.
Wegler U,Sens-Schonfelder C.2007.Fault zone monitoring with passive image interferometry[J].Geophys J Int,168(3):1029--1033.
Xu Z J,Song X D.2009.Temporal changes of surface wave velocity associated with major Sumatra earthquakes from am-bient noise correlation[J].Proc Natl Acad Sci USA,106(34):14207--14212,doi:10.1073/pnas.0901164106.
Yang Y,Ritzwoller M H,Levshin A L,Shapiro N M.2007.Ambient noise Rayleigh wave tomography across Europe[J].Geophys J Int,168(1):259--274.
Yao H J,van der Hilst R D,de Hoop M V.2006.Surface-wave array tomography in SE Tibet from ambient seismicnoise and two-station analysis-I.Phase velocity maps[J].Geophys J Int,166(2):732--744.
Zheng S,Sun X,Song X,Yang Y,Ritzwoller M H.2008.Surface wave tomography of China from ambient seismic[J].Geochem Geophys Geosyst,9(5):1525--2027.
Zheng Y,Yang Y,Ritzwoller M H,Zheng X,Xiong X,Li Z.2010.Crustal structure of the northeastern Tibetan plat-eau,the Ordos block and the Sichuan basin from ambient noise tomography[J].Earthq Sci,23(5):465--476.
刘志坤,黄金莉.2010.利用背景噪声互相关研究汶川地震震源区地震波速度变化[J].地球物理学报,53(4):853--863.
赵盼盼.2011.汶川地震区地壳速度相对变化的地震环境噪声自相关研究[D].北京:中国地震局地质研究所:1--50.
郑秀芬,欧阳飚,张东宁,姚志祥,梁建宏,郑洁.2009.“国家数字测震台网数据备份中心”技术系统建设及其对汶川大地震研究的数据支撑[J].地球物理学报,52(5):1412--1417.
郑现,赵翠萍,周连庆,郑斯华.2012.中国大陆中东部地区基于背景噪声的瑞利波层析成像[J].地球物理学报,55(6):1919--1928.
Bensen G B,Ritzwoller M H,Barmin M P,Levshin A L,Lin F,Moschetti M P,Shapiro N M,Yang Y.2007.Process-ing seismic ambient noise data to obtain reliable broad-band surface wave dispersion measurements[J].Geophys JInt,169(3):1239--1260.
Bensen G B,Ritzwoller M H,Shapiro N M.2008.Broadband ambient noise surface wave tomography across the UnitedStates[J].J Geophys Res,113(B5306):1--21.
Brenguier F N,Shapiro N M,Campillo M,Ferrazzini V,Duputel Z,Coutant O,Nercessian A.2008a.Towards foresca-sting volcanic eruptions using seismic noise[J].Nat Geosci,1(2):126--130.
Brenguier F N,Campillo M,Hadziioannou C,Shapiro N M,Nadeau R M,Larose E.2008b.Postseismic relaxationalong the San Andreas Fault at Parkfield from continuous seismological observations[J].Science,321(5895):1478.
Campillo M,Paul A.2003.Long-range correlations in the diffuse seismic coda[J].Science,299(5606):547--549.
Chen J H,Froment B,Liu Q Y,Campillo M.2010.Distribution of seismic wave speed changes associated with the12May2008MW7.9Wenchuan earthquake[J].Geophys Res Lett,37(18):L18302,doi:10.1029/2010GL044582.
Fang L H,Wu J P,Ding Z F,Panza G F.2010.High resolution Rayleigh wave group velocity tomography in North Chi-na from ambient seismic noise[J].Geophys J Int,181(2):1171--1182.
Kang T S,Shin J S.2006.Surface-wave tomography from ambient seismic noise of accelerograph networks in southernKorea[J].Geophys Res Lett,33(L17303):1--5.
Levshin A L,Ritzwoller M H.2001.Automated detection,extraction,and measurement of regional surface waves[J].Pure Appl Geophys,158(8):1531--1545.
Li H,Su W,Wang C,Huang Z.2009.Ambient noise Rayleigh wave tomography in western Sichuan and eastern Tibet[J].Earth Planet Sci Lett,282(1--4):201--211.
Lin F,Ritzwoller M H,Townend J,Bannister S,Savage M K.2007.Ambient noise Rayleigh wave tomography of NewZealand[J].Geophys J Int,170(2):649--666.
Lin F,Moschetti M P,Ritzwoller M H.2008.Surface wave tomography of the western United States from ambient seis-mic noise:Rayleigh and Love wave phase velocity maps[J].Geophys J Int,173(1):281--298.
Lobkis O I,Weave R L.2001.On the emergence of the Green’s function in the correlations of a diffuse field[J].JAcoust Soc Amer,110(6):3011--3017.
Nishida K,Montagner J P,Hitoshi K.2009.Global surface wave tomography using seismic hum[J].Science,326(5949):112.
Shapiro N M,Ritzwoller M H.2002.Monte-Carlo inversion for a global shear-velocity model of the crust and upper man-tle[J].Geophys J Int,151(1):88--105.
Shapiro N M,Campillo M.2004.Emergence of broadband Rayleigh waves from correlations of the ambient seismic noise[J].Geophys Res Lett,31(7):1--5.
Shapiro N M,Campillo M,Stehly L,Ritzwoller M H.2005.High-resolution surface-wave tomography from ambientseismic noise[J].Science,305(5681):233--236.
Sun X L,Song X D,Zheng S H,Yang Y J,Ritzwoller M H.2010.Three dimensional shear wave velocity structure ofthe crust and upper mantle beneath China from ambient noise surface wave tomography[J].Earthq Sci,23(5):449--463.
Weaver R L,Lobkis O I.2001.Ultrasonics without a source Thermal fluctuation correlations at MHz frequencies[J].Phys Rev Lett,87(13):134301.
Wegler U,Sens-Schonfelder C.2007.Fault zone monitoring with passive image interferometry[J].Geophys J Int,168(3):1029--1033.
Xu Z J,Song X D.2009.Temporal changes of surface wave velocity associated with major Sumatra earthquakes from am-bient noise correlation[J].Proc Natl Acad Sci USA,106(34):14207--14212,doi:10.1073/pnas.0901164106.
Yang Y,Ritzwoller M H,Levshin A L,Shapiro N M.2007.Ambient noise Rayleigh wave tomography across Europe[J].Geophys J Int,168(1):259--274.
Yao H J,van der Hilst R D,de Hoop M V.2006.Surface-wave array tomography in SE Tibet from ambient seismicnoise and two-station analysis-I.Phase velocity maps[J].Geophys J Int,166(2):732--744.
Zheng S,Sun X,Song X,Yang Y,Ritzwoller M H.2008.Surface wave tomography of China from ambient seismic[J].Geochem Geophys Geosyst,9(5):1525--2027.
Zheng Y,Yang Y,Ritzwoller M H,Zheng X,Xiong X,Li Z.2010.Crustal structure of the northeastern Tibetan plat-eau,the Ordos block and the Sichuan basin from ambient noise tomography[J].Earthq Sci,23(5):465--476.
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