【摘要】 采用双轨处理模式对8景ENVISAT降轨数据进行永久散射体(PS)时间序列处理,获得了2009年4月6日意大利拉奎拉(L’Aquila)Mw 6.3级地震区域的PS时序差分干涉图和形变场。结合Delaunay三角形剖分算法对破裂区的形变过程进行数值分析,结果表明:①本次地震变形最强烈、地表破裂发生的区域是一个地势相对较低的椭圆形洼地。破裂主要沿震中的东南方向传播,面积约22×14km2,方向约135°。②地震产生的形变量集中在破裂区,主要在震时及震后形成,位移场视线向下沉量达150mm。③破裂区位移场数值分析表明,本文提出的数据处理策略较完整地揭示了此次地震位移场变化的全过程,在8景雷达数据所跨时间段内,震前2008年4月与2009年2月两景资料显示,研究区位移场变化不明显,2009年2月至震后的2009年4月的图像显示,震中区形变场快速变化,沉降量达130mm;6～7月,形变场的沉降速度明显减缓,8月30日最后一景资料显示,沉降速度出现加速,破裂区总下沉量达150mm。更多还原

【Abstract】 Using 8 descending track Envisat ASAR images,time series of different interferograms and consequent co-seismic deformation field of the L’Aquila earthquake(Mw 6.3 on 6 April 2009) were obtained by PSInSAR method.Furthermore,deformation processes of rupture zone were numerically analyzed using Delaunay triangulation algorithms based on above results.The results show that:① The rupture center located at a low elliptic depression region.The cracking propagated along southeastward direction with an orientation of 135° and covered about 22×14 km2.② The deformation area was mainly located in the rupture center,which was formed at the epoch of earthquake and thereafter.The displacement of rupture center in radar line of sight was as high as 150 mm.③ The numerical analysis results of the entire deformation process in rupture zone detected by Envisat show that: from Jan.2008 to Feb.2009 before the earthquake,the ground deformation of target zone was not significant;from Feb.to Apr.2009 after the shock,the deformation field of rupture zone changed rapidly with a maximum of subsidence of 130 mm;from Jun.to Jul.2009,the settling velocity of deformation field was slowing-down;while on 30 Aug.2009,the subsidence rate shown from last SAR image turns to accelerate,and total settlement amount in rupture zone reached 150 mm.更多还原