地震学报
地震學報
지진학보
Acta Seismologica Sinica
2015年
5期
796-805
,共10页
日本东北 MW9.0 地震%合成孔径雷达干涉测量%数据重采样%同震滑动分布
日本東北 MW9.0 地震%閤成孔徑雷達榦涉測量%數據重採樣%同震滑動分佈
일본동북 MW9.0 지진%합성공경뢰체간섭측량%수거중채양%동진활동분포
Tohoku MW 9.0 earthquake%synthetic aperture radar interferome-try%data resampling%coseismic slip distribution
本文首先对 Envisat／ASAR 数据进行干涉处理，获取2011年日本东北 MW 9．0地震的地表 InSAR 同震形变场；然后通过对 InSAR 同震形变数据重采样方法的深入分析，选择条纹率法结合干涉图的空间相干性对 InSAR 同震形变数据进行重采样；最后基于弹性半空间位错模型，联合 InSAR 与 GPS 形变数据，采用最小二乘法反演发震断层的滑动分布．研究结果表明：考虑相干性的条纹率重采样方法，更适用于形变场中存在除断层外的有限边界、且形变场范围较大的 InSAR 数据重采样处理；断层滑动主要发生在地表以下50 km 范围内，最大滑动量为49．9 m，矩张量为4．89×1022 N·m，所对应的矩震级为 MW 9．1，与地震学反演的结果比较吻合．
本文首先對 Envisat／ASAR 數據進行榦涉處理，穫取2011年日本東北 MW 9．0地震的地錶 InSAR 同震形變場；然後通過對 InSAR 同震形變數據重採樣方法的深入分析，選擇條紋率法結閤榦涉圖的空間相榦性對 InSAR 同震形變數據進行重採樣；最後基于彈性半空間位錯模型，聯閤 InSAR 與 GPS 形變數據，採用最小二乘法反縯髮震斷層的滑動分佈．研究結果錶明：攷慮相榦性的條紋率重採樣方法，更適用于形變場中存在除斷層外的有限邊界、且形變場範圍較大的 InSAR 數據重採樣處理；斷層滑動主要髮生在地錶以下50 km 範圍內，最大滑動量為49．9 m，矩張量為4．89×1022 N·m，所對應的矩震級為 MW 9．1，與地震學反縯的結果比較吻閤．
본문수선대 Envisat／ASAR 수거진행간섭처리，획취2011년일본동북 MW 9．0지진적지표 InSAR 동진형변장；연후통과대 InSAR 동진형변수거중채양방법적심입분석，선택조문솔법결합간섭도적공간상간성대 InSAR 동진형변수거진행중채양；최후기우탄성반공간위착모형，연합 InSAR 여 GPS 형변수거，채용최소이승법반연발진단층적활동분포．연구결과표명：고필상간성적조문솔중채양방법，경괄용우형변장중존재제단층외적유한변계、차형변장범위교대적 InSAR 수거중채양처리；단층활동주요발생재지표이하50 km 범위내，최대활동량위49．9 m，구장량위4．89×1022 N·m，소대응적구진급위 MW 9．1，여지진학반연적결과비교문합．
To determine the causative fault slip distribution of the Tohoku MW 9.0 earthquake in Japan,the coseismic deformation field of this earthquake was obtained with synthetic aperture radar interferometry (InSAR)technique based on Envisat/ASAR data.With detailed analysis and comparison of differ-ent methods used to resample InSAR deformation data,the fringe rate method taking into account spatial coherence of the interferogram was chosen for data resampling.Based on the elastic half-space dislocation model,the slip distribu-tion of causative fault was inverted from InSAR and GPS data using the least squares method.The research results show that the fringe rate with coherence method is more suitable for data resampling of wider range InSAR deformation field,within which there are finite boundaries except fault.The majority of the fault slips occurred mainly in the range of 50 km below the surface,and the maximal slip on the fault is 49.9 m,meanwhile,the moment tensor is 4.89 × 1022 N·m,the corresponding moment magnitude is MW 9.1.All these are con-sistent well with the results from seismological inversion, suggesting this inversion result in this study is reliable.
