利用断层自动剖分技术的2008年青海大柴旦Mw6.3级地震InSAR反演研究
|
摘要
2008-11-10青海大柴旦地区发生了Mw 6.3级地震,其发震断层位于青藏高原东北缘的大柴旦-宗务隆山断裂带。利用欧空局Envisat/ASAR卫星雷达影像数据,采用二通差分干涉技术获得了地震的同震地表形变场,基于1D协方差函数估计InSAR同震形变场的中误差为0.52cm,方差-协方差衰减距离为5.9km。在此基础上,采用弹性半空间矩形位错模型进行断层几何参数反演,并利用断层自动剖分技术确定了地震的最佳同震滑动分布模型。结果表明,该地震的震源机制解为走向107.19°,倾角56.57°,以逆冲为主兼具少量右旋走滑分量;滑动分布主要发生在10～20km深度范围内,最大滑动量为0.51m,释放的能量为4.3×1018 Nm。
On 10th November 2008,a Mw 6.3 earthquake occurred in the Dachaidan region,Qinghai province,whose seismogenic fault is situated in Dachaidan-Zongwulongshan fault zone which is located on the northeastern margin of Qinghai-Tibet Plateau.A coseismic deformation field of the earthquake is constructed from ESA Envisat/ASAR radar images using 2-pass differential interferometry.The root mean square error of the InSAR coseismic deformation field is 0.52 cm with a spatial decay distance of 5.9 km,which are estimated using 1D variance-covariance function.The fault geometry is inverted using a rectangle dislocation model in the elastic half-space and the optimal coseismic fault slip model is determined based on the automated fault discretization method using the observed InSAR data.The inverted results showed that the earthquake occurred on the southern wall of Dacaidan-zongwulongshan fault with a strike of 107.19° and a dip of 56.57°,which is dominated by thrust movement with a little right-lateral strike-slip component.Most of the slip is observed at a depth of 10-20 km,and the maximal slip is 0.51 m.The inverted geodetic moment is 4.3×1018 Nm.
On 10th November 2008,a Mw 6.3 earthquake occurred in the Dachaidan region,Qinghai province,whose seismogenic fault is situated in Dachaidan-Zongwulongshan fault zone which is located on the northeastern margin of Qinghai-Tibet Plateau.A coseismic deformation field of the earthquake is constructed from ESA Envisat/ASAR radar images using 2-pass differential interferometry.The root mean square error of the InSAR coseismic deformation field is 0.52 cm with a spatial decay distance of 5.9 km,which are estimated using 1D variance-covariance function.The fault geometry is inverted using a rectangle dislocation model in the elastic half-space and the optimal coseismic fault slip model is determined based on the automated fault discretization method using the observed InSAR data.The inverted results showed that the earthquake occurred on the southern wall of Dacaidan-zongwulongshan fault with a strike of 107.19° and a dip of 56.57°,which is dominated by thrust movement with a little right-lateral strike-slip component.Most of the slip is observed at a depth of 10-20 km,and the maximal slip is 0.51 m.The inverted geodetic moment is 4.3×1018 Nm.
引文
[1]张培震,邓起东,张国民.中国大陆的强震运动与活动地块[J].中国科学(D辑),2003,33(增刊):12-20
[2]张培震.中国大陆岩石圈最新构造变动与地震灾害[J].第四纪研究,1999(5):404-413
[3]李智敏,屠泓为,田勤俭,等.2008年青海大柴旦6.3级地震及其发震背景研究[J].地球物理学进展,2010,25(3):768-774
[4]刘小龙,袁道阳.青海德令哈巴音郭勒河断裂带的新活动特征[J].西北地震学报,2004,26(4):303-308
[5]Funning G L,Wright T J,Jackson J A,et al.Sur-face Displacements and Source Parameters of the2003BAM(Iran)Earthquake from Envisat Ad-vanced Synthetic Aperture Radar Imagery[J].Jour-nal of Geophysical Research,2005,110(B09406),doi:10.1029/2005JB0338
[6]温扬茂,许才军.基于敏感度的迭代拟合法反演玛尼Ms7.9级地震滑动分布[J].武汉大学学报.信息科学版,2009,34(6):732-735
[7]Simons M,Fialko Y,Rivera L.Coseismic Deform-ation from the 1999Mw 7.1Hector Mine,Califor-nia,Earthquake as Inferred from InSAR and GPSObservations[J].Bulletin of the Seismological Soci-ety of America,2002,92(4):1 390-1 402
[8]Barnhart W D,Lohman R B.Automated FaultModel Discretization for Inversions for CoseismicSlip Distribution[J].Journal of Geophysical Re-search,2010,115(B10419),doi:10.1029/2010JB007545
[9]Rosen P A,Henley S,Peltzer G,et al.UpdatedRepeat orbit Interferometry Package Released[J].EOS,Transaction American Geophysical Union,2004,85(5),doi:10.1029/2004EO050004
[10]Farr M,Rosen A,Caro E.The Shuttle Radar To-pography Mission[J].Review Geophysics,2007,45(RG2004),doi:10.1029/2005RG000183
[11]Parsons B,Wright T,Rowe P,et al.The 1994Sefidabeh(Eastern Lran)Earthquakes Revisited:New Evidence from Satellite Radar Interferometryand Carbonate Dating About the Growth of an Ac-tive Fold Above a Blind Thrust Fault[J].Geophysi-cal.Journal International,2006,164:202-217
[12]Wright T,Fielding E,Parsons B.Triggered Slip:Observations of the 17August 1999Izmit(Turkey)Earthquake Using Radar Interferometry[J].Geo-physical Research Letters,2001,28(6):1 079-1 082
[13]Fukahata Y,Nishitani A,Mastu’ura M.GeodeticData Inversion Using ABIC to Estimate Slip HistoryDuring One Earthquake Cycle with ViscoelasticSlip-response Functions[J].Geophysical Journal In-ternational,2004,156:140-153
[14]Johnson K M,Hsu Y,Segall P,et al.Fault Geom-etry and Slip Distribution of the 1999Chi-chi,Tai-wan Earthquake Imaged from Inversion of GPS Data[J].Geophysical Research Letters,2001,28(11):2 285-2 288
[15]Du Y,Segall P.Comparison of Various InversionTechniques as Applied to the Determination of aGeophysicl Deformation Model for the 1983BorahPeak Earthquake[J].Bulletin of the Seismology So-ciety of American,1992,82:1 840-1 866
[16]许才军,林敦灵,温扬茂.利用InSAR数据的汶川地震形变场提取及分析,武汉大学学报.信息科学版,2010,35(10):1 138-1 142
[2]张培震.中国大陆岩石圈最新构造变动与地震灾害[J].第四纪研究,1999(5):404-413
[3]李智敏,屠泓为,田勤俭,等.2008年青海大柴旦6.3级地震及其发震背景研究[J].地球物理学进展,2010,25(3):768-774
[4]刘小龙,袁道阳.青海德令哈巴音郭勒河断裂带的新活动特征[J].西北地震学报,2004,26(4):303-308
[5]Funning G L,Wright T J,Jackson J A,et al.Sur-face Displacements and Source Parameters of the2003BAM(Iran)Earthquake from Envisat Ad-vanced Synthetic Aperture Radar Imagery[J].Jour-nal of Geophysical Research,2005,110(B09406),doi:10.1029/2005JB0338
[6]温扬茂,许才军.基于敏感度的迭代拟合法反演玛尼Ms7.9级地震滑动分布[J].武汉大学学报.信息科学版,2009,34(6):732-735
[7]Simons M,Fialko Y,Rivera L.Coseismic Deform-ation from the 1999Mw 7.1Hector Mine,Califor-nia,Earthquake as Inferred from InSAR and GPSObservations[J].Bulletin of the Seismological Soci-ety of America,2002,92(4):1 390-1 402
[8]Barnhart W D,Lohman R B.Automated FaultModel Discretization for Inversions for CoseismicSlip Distribution[J].Journal of Geophysical Re-search,2010,115(B10419),doi:10.1029/2010JB007545
[9]Rosen P A,Henley S,Peltzer G,et al.UpdatedRepeat orbit Interferometry Package Released[J].EOS,Transaction American Geophysical Union,2004,85(5),doi:10.1029/2004EO050004
[10]Farr M,Rosen A,Caro E.The Shuttle Radar To-pography Mission[J].Review Geophysics,2007,45(RG2004),doi:10.1029/2005RG000183
[11]Parsons B,Wright T,Rowe P,et al.The 1994Sefidabeh(Eastern Lran)Earthquakes Revisited:New Evidence from Satellite Radar Interferometryand Carbonate Dating About the Growth of an Ac-tive Fold Above a Blind Thrust Fault[J].Geophysi-cal.Journal International,2006,164:202-217
[12]Wright T,Fielding E,Parsons B.Triggered Slip:Observations of the 17August 1999Izmit(Turkey)Earthquake Using Radar Interferometry[J].Geo-physical Research Letters,2001,28(6):1 079-1 082
[13]Fukahata Y,Nishitani A,Mastu’ura M.GeodeticData Inversion Using ABIC to Estimate Slip HistoryDuring One Earthquake Cycle with ViscoelasticSlip-response Functions[J].Geophysical Journal In-ternational,2004,156:140-153
[14]Johnson K M,Hsu Y,Segall P,et al.Fault Geom-etry and Slip Distribution of the 1999Chi-chi,Tai-wan Earthquake Imaged from Inversion of GPS Data[J].Geophysical Research Letters,2001,28(11):2 285-2 288
[15]Du Y,Segall P.Comparison of Various InversionTechniques as Applied to the Determination of aGeophysicl Deformation Model for the 1983BorahPeak Earthquake[J].Bulletin of the Seismology So-ciety of American,1992,82:1 840-1 866
[16]许才军,林敦灵,温扬茂.利用InSAR数据的汶川地震形变场提取及分析,武汉大学学报.信息科学版,2010,35(10):1 138-1 142
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