利用地震矩张量和GPS速度反演南极半岛现今构造运动特征
|
摘要
根据南极半岛地区50年以来发生的9次MW>5级的地震机制解资料,利用Kostrov公式计算了地震主应变率及主应变率的方向,利用SCAR国际GPS会战数据得到的GPS速度场资料在椭球面上进行计算得到了南极半岛的最大剪应变率、主应变率、面膨胀率等应变率状态参数;经过综合分析初步得到了南极半岛地区现今的形变特征,认为南极半岛地区的应变率状态以拉张为主,压缩为辅,结合地质构造资料认为该地区近期发生大震的可能性不大.
According to the document of seismic mechanism of which nine seismics are larger than five during the last fifty years in Antarctic Peninsula,the seismic principal rates of stresses and their orientations are given with Kostrov formulation.The principal rates of shear stresses and bulks are also given after the velocities of GPS from international GPS campaign being processed on reference ellipsoid.When data are carefully examined and analyzed,the conclusions show that the principal rates of stresses are mainly extensional but not compressible.It seems that large seismic would not happen in a not long future in Antarctic Peninsula.
According to the document of seismic mechanism of which nine seismics are larger than five during the last fifty years in Antarctic Peninsula,the seismic principal rates of stresses and their orientations are given with Kostrov formulation.The principal rates of shear stresses and bulks are also given after the velocities of GPS from international GPS campaign being processed on reference ellipsoid.When data are carefully examined and analyzed,the conclusions show that the principal rates of stresses are mainly extensional but not compressible.It seems that large seismic would not happen in a not long future in Antarctic Peninsula.
引文
[1]Molnar P,Deng Qidong.Faulting associated with large earthquakes and the average rate of deformation in central and eastern Asia[J].J GeophysRes,1984,89:6203~6227.
[2]杜继亮,许才军,李志才.喜马拉雅块体现今运动学特征的地震矩张量反演分析[J].武汉大学学报(信息科学版),2002,27(3):261~264.
[3]许才军,董立祥,李志才.华北地区地壳形变的GPS及地震矩张量反演分析[J].武汉测绘科技大学学报,2000,25(6):471~475.
[4]Brune,James N.Seismic moment seismicity and rate of slip along major fault zones[J].Journal of Geophysical Research,1968,73:777~784.
[5]Kostrov V V.Seismic Moment,Energy of Earthquakes and the Seismic Flow of Rock[J].Phys Solid Earth,1974,10:23~44.
[6]Aki K.Re-evaluation of stress drop and seismic energy using a newmodel of earthquake faulting,in Source Mechanismand Earthquake Prediction[J]Tectonophysics,1980,13:423~446.
[7]顾国华,孙汉荣,孙惠娟.利用GPS地形变在大地坐标系中计算应变[J].地壳变形与地震.1998,18(3):26~31.
[8]Lee D K,Jin YK,Kim Y.Seismicity and tectonics around the northern Antarctic Peninsula from King Sejong station data[J].Antarctic Sci-ence.2000,12(2):196~204.
[9]Balanya J C,Galindo-Zaldivar J A,Jabaloy,et al.Structure of the South Powell Ridge(NE Antarctic Peninsula):newclues for changing tectonicregimes near the Scotia/Antarctica Plate boundary[J].Geo-Marine Letters,1999,18:215~224.
[10]Barbot S,Fialko Y,Bock Y.Postseismic deformation due to M-w6.0 2004 Parkfield earthquake:Stress-driven creep on a fault with spatiallyvariable rate-and-state friction parameters[J].J Geophys Res,2009,114:1~26.
[11]Stich D,Serpelloni E,Mancilla F,et al.Kinematics of the Iberia-Maghreb plate contact from seismic moment tensors and GPS observations[J].Tectonophysics,2006,426:295~317.
[2]杜继亮,许才军,李志才.喜马拉雅块体现今运动学特征的地震矩张量反演分析[J].武汉大学学报(信息科学版),2002,27(3):261~264.
[3]许才军,董立祥,李志才.华北地区地壳形变的GPS及地震矩张量反演分析[J].武汉测绘科技大学学报,2000,25(6):471~475.
[4]Brune,James N.Seismic moment seismicity and rate of slip along major fault zones[J].Journal of Geophysical Research,1968,73:777~784.
[5]Kostrov V V.Seismic Moment,Energy of Earthquakes and the Seismic Flow of Rock[J].Phys Solid Earth,1974,10:23~44.
[6]Aki K.Re-evaluation of stress drop and seismic energy using a newmodel of earthquake faulting,in Source Mechanismand Earthquake Prediction[J]Tectonophysics,1980,13:423~446.
[7]顾国华,孙汉荣,孙惠娟.利用GPS地形变在大地坐标系中计算应变[J].地壳变形与地震.1998,18(3):26~31.
[8]Lee D K,Jin YK,Kim Y.Seismicity and tectonics around the northern Antarctic Peninsula from King Sejong station data[J].Antarctic Sci-ence.2000,12(2):196~204.
[9]Balanya J C,Galindo-Zaldivar J A,Jabaloy,et al.Structure of the South Powell Ridge(NE Antarctic Peninsula):newclues for changing tectonicregimes near the Scotia/Antarctica Plate boundary[J].Geo-Marine Letters,1999,18:215~224.
[10]Barbot S,Fialko Y,Bock Y.Postseismic deformation due to M-w6.0 2004 Parkfield earthquake:Stress-driven creep on a fault with spatiallyvariable rate-and-state friction parameters[J].J Geophys Res,2009,114:1~26.
[11]Stich D,Serpelloni E,Mancilla F,et al.Kinematics of the Iberia-Maghreb plate contact from seismic moment tensors and GPS observations[J].Tectonophysics,2006,426:295~317.
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