基于Sentinel-1A数据反演2015年新疆皮山M_W6.5地震断层滑动分布
|
摘要
使用Sentinel-1A卫星观测的2015年新疆皮山地震震前震后一对SAR影像,提取该地震的同震形变场。结合Okada位错模型,在考虑渐变入射角和解缠基准偏差的情况下,反演本次地震的断层滑动分布。结果表明,皮山地震是小倾角逆冲型地震,断层破裂开始于地表以下约5km处,最大滑动量为0.76m,高滑区集中于深度9~14km,累计释放地震矩达5.14×10~(18),相当于矩阵级MW6.47。
In this study,apair of SAR imagestaken before and after the Pishan earthquake acquired from the Sentinel-1Asatellite are used to extract the coseismic deformation field.Based on the above coseismic deformation field and the Okada model,considering the varying incidence angle and unwrapping datum error,we inverse the fault slip distribution of this earthquake.The inversion results indicate that the Pishan earthquake is a thrust earthquake with smaller dip,the fault ruptures 5km under the surface,and the maximum slip is about 0.76 m,and the main slip area is at the depth of 9-14 km.The estimated seismic moment is 5.14×10~(18),approximately equivalent to the magnitude of M_W6.47.
In this study,apair of SAR imagestaken before and after the Pishan earthquake acquired from the Sentinel-1Asatellite are used to extract the coseismic deformation field.Based on the above coseismic deformation field and the Okada model,considering the varying incidence angle and unwrapping datum error,we inverse the fault slip distribution of this earthquake.The inversion results indicate that the Pishan earthquake is a thrust earthquake with smaller dip,the fault ruptures 5km under the surface,and the maximum slip is about 0.76 m,and the main slip area is at the depth of 9-14 km.The estimated seismic moment is 5.14×10~(18),approximately equivalent to the magnitude of M_W6.47.
引文
[1]CENC.[EB/OL].http:∥www.cea.gov.cn/publish/dizhenj/468/553/101527/index.html
[2]USGS.[EB/OL].http:∥earthquake.usgs.gov/earthquakes/eventpage
[3]Wen Y M,Xu C J,Liu Y,et al.Deformation and Source Parameters of the 2015 MW6.5 Earthquake in Pishan,Western China,from Sentinel-1A and ALOS-2data[J].Remote Sensing,2016,134(8):1-14
[4]Deng Q.Map of Active Tectonics in China[M].Beijing:Seismological Press,2007
[5]Zhou Y,Wang W M,Xiong L,et al.Rupture Process of12February 2014,Yutian MW6.9 Earthquake and Stress Change on nearby Faults[J].Chin J Geophys,2015,58(1):184-193
[6]ESA.[EB/OL].http:∥www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-1
[7]李永生,冯万鹏,张景发,等.2014年美国加州纳帕MW6.1地震断层参数的Sentinel-1AInSAR反演[J].地球物理学报,2015,58(7):2 339-2 349(Li Yongsheng,Feng Wanpeng,Zhang Jingfa,et al.Coseismic Slip of the 2014MW6.1Napa,California Earthquake Revealed by Sentinel-1AInSAR[J].Chinese Journal of Geophysics,2015,58(7):2 339-2 349)
[8]ESA.[EB/OL].https:∥scihub.copernicus.eu/s2/#/home
[9]Massonnet D,Rossi M,Carmona C.The Displacement Filed of the Landers Earthquake Mapped by Radar Interferometry[J].Nature,1993,364(8):138-142
[10]冯万鹏,许力生,李振洪.2008年10月当雄MW6.3级地震断层参数的InSAR反演及其构造意义[J].地球物理学报,2010,53(5):1 134-1 142(Feng Wanpeng,Xu Lisheng,Li Zhenhong.Fault Parameters of the October 2008Damxung MW6.3Earthquake from InSAR Inversion and Its Tectonic Implication[J].Chinese Journal of Geophysics,2010,53(5):1 134-1 142)
[11]Farr M,Rosen A,Caro E.The Shuttle Radar Topography Mission[J].Reviews of Geophysics,2007,45(2):33
[12]Chen C W,Zebker H A.Two-Dimensional Phase Unwrapping with Use of Statistical Models for Cost Functions in Nonlinear Optimization[J].Journal of the Optical Society of America A:Optics,Image Science and Vision,2001,18(S2):338-351
[13]Lohman R B,Simons M.Some Thoughts on the Use of InSAR Data to Constrain Models of Surface Deformation:Noise Structure and Data Downsampling[J].Geochem Geophys Geosyst,2005,6(1):359-361
[14]Clarke P J,Paradissis D,Briole P,et al.Geodetic Investigation of the 13 May 1995Kozani-Grevena(Greece)Earthquake[J].Geophysical Research Letters,1997,24(6):707-710
[15]Okada Y.Surface Deformation Due to Shear and Tensile Faults in a Half-Space[J].Bulletin of the Seismological Society of America,1985,75(4):1 135-1 154
[16]Harris R A,Segall P.Detection of a Locked Zone at Depth on the Parkfield,California,Segment of the San Andreas Fault[J].Journal of Geophysical Research:Solid Earth(1978-2012),1987,92(B8):7 945-7 962
[2]USGS.[EB/OL].http:∥earthquake.usgs.gov/earthquakes/eventpage
[3]Wen Y M,Xu C J,Liu Y,et al.Deformation and Source Parameters of the 2015 MW6.5 Earthquake in Pishan,Western China,from Sentinel-1A and ALOS-2data[J].Remote Sensing,2016,134(8):1-14
[4]Deng Q.Map of Active Tectonics in China[M].Beijing:Seismological Press,2007
[5]Zhou Y,Wang W M,Xiong L,et al.Rupture Process of12February 2014,Yutian MW6.9 Earthquake and Stress Change on nearby Faults[J].Chin J Geophys,2015,58(1):184-193
[6]ESA.[EB/OL].http:∥www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Sentinel-1
[7]李永生,冯万鹏,张景发,等.2014年美国加州纳帕MW6.1地震断层参数的Sentinel-1AInSAR反演[J].地球物理学报,2015,58(7):2 339-2 349(Li Yongsheng,Feng Wanpeng,Zhang Jingfa,et al.Coseismic Slip of the 2014MW6.1Napa,California Earthquake Revealed by Sentinel-1AInSAR[J].Chinese Journal of Geophysics,2015,58(7):2 339-2 349)
[8]ESA.[EB/OL].https:∥scihub.copernicus.eu/s2/#/home
[9]Massonnet D,Rossi M,Carmona C.The Displacement Filed of the Landers Earthquake Mapped by Radar Interferometry[J].Nature,1993,364(8):138-142
[10]冯万鹏,许力生,李振洪.2008年10月当雄MW6.3级地震断层参数的InSAR反演及其构造意义[J].地球物理学报,2010,53(5):1 134-1 142(Feng Wanpeng,Xu Lisheng,Li Zhenhong.Fault Parameters of the October 2008Damxung MW6.3Earthquake from InSAR Inversion and Its Tectonic Implication[J].Chinese Journal of Geophysics,2010,53(5):1 134-1 142)
[11]Farr M,Rosen A,Caro E.The Shuttle Radar Topography Mission[J].Reviews of Geophysics,2007,45(2):33
[12]Chen C W,Zebker H A.Two-Dimensional Phase Unwrapping with Use of Statistical Models for Cost Functions in Nonlinear Optimization[J].Journal of the Optical Society of America A:Optics,Image Science and Vision,2001,18(S2):338-351
[13]Lohman R B,Simons M.Some Thoughts on the Use of InSAR Data to Constrain Models of Surface Deformation:Noise Structure and Data Downsampling[J].Geochem Geophys Geosyst,2005,6(1):359-361
[14]Clarke P J,Paradissis D,Briole P,et al.Geodetic Investigation of the 13 May 1995Kozani-Grevena(Greece)Earthquake[J].Geophysical Research Letters,1997,24(6):707-710
[15]Okada Y.Surface Deformation Due to Shear and Tensile Faults in a Half-Space[J].Bulletin of the Seismological Society of America,1985,75(4):1 135-1 154
[16]Harris R A,Segall P.Detection of a Locked Zone at Depth on the Parkfield,California,Segment of the San Andreas Fault[J].Journal of Geophysical Research:Solid Earth(1978-2012),1987,92(B8):7 945-7 962