【作者】 张国宏；

【导师】 单新建；

【作者基本信息】 中国地震局地质研究所 ， 构造地质学， 2006， 硕士

【摘要】 本文的研究结合了现代空间对地观测技术特别是差分合成孔径雷达干涉测量技术(Differential Interferometry Synthetic Aperture Radar, D-InSAR)、数值模拟、有限元算法及远程计算技术,对发生在二十世纪末我国大陆的一次强震进行了研究。采用成熟的的空间对地观测技术D-InSAR,获取了1997年Ms7.9玛尼地震震前、同震D-InSAR干涉形变场;利用有限元算法和软件,对震前D-InSAR干涉形变场进行了数值模拟,获得关于玛尼地震两盘介质力学参数等的一些新认识;基于Okada弹性半空间位错理论,在网络环境下开发了D-InSAR同震干涉形变场远程模拟系统,并对玛尼地震同震形变场进行了解析模拟,获取了此次地震的部分几何学及运动学参数。在吸收和借鉴前人工作成果的基础上,本论文的主要贡献在于取得了如下的结果和认识:运用差分干涉测量技术(D-InSAR)获取了西藏玛尼7.9级地震震前、同震干涉形变场1997年11月8日西藏玛尼7.9级地震发生在羌塘盆地北缘,NEE向玛尔盖茶卡-若拉错断裂带上。羌塘地区,藏语指藏北无人居住的地方,那里气候寒冷,空气稀薄,野外条件非常艰苦,且方圆几百公里内无形变观测台,这些现实情况限制了我们对孕震区地表形变场、活动断层变形等问题的深入认识。而星载D-INSAR测量技术将不受这些因素的限制,在利用获取空间形变场演化方面具有不可替代的优势。因此,收集了1995年1月至2000年12月期间的14景欧空局ERS-1/2雷达卫星数据。ERS-1 SAR数据分别有:2889/19960415、2907 /19960415;ERS-2 SAR数据分别有:2889/19960416、2907/19960416、2889/19970121、2907/19970121、2889/19970610、2907/19970610、2889/19970819、2907/19970819、2889/19971202、2907/19971202、2889/19980421、2907/19980421。通过采用“三通”、“四通”差分干涉模式,对SAR数据进行了处理,即由震前相差一天的两景SAR图像(Tandem数据)产生干涉图,通过解缠获取高精度DEM,来消除另一幅干涉图的地形影响,以达到减少地形残留相位,提高形变量观测精度的目的。由于两幅SAR图像是在相邻轨道上获取的,造成入射角、星下平台方向和线采样距等卫星参数有微小的差异,为保证干涉处理的精度,必须统一成像处理参数。通过选取不同时间和不同时间间隔的SAR图像,获取了震前—震时的动态干涉形变图像。运用有限元算法和有限元软件(ansys9.0),对1997年Ms7.9玛尼地震D-InSAR震前干涉形变场进行了数值试验由于地震涉及从应变能积累到释放,从断层蠕滑到错动等诸多复杂的过程;地球内部即有处于流体状态的地幔热物质,也有刚性的岩石圈,还有状态不太稳定的断层介质。因此从更多还原

【Abstract】 This thesis presents a study of a great earthquake, which happened in the mainland of China at the end of 20th Century. Several theories and technologies are combined in order to do the research, including modern space geodetic techniques specially D-InSAR (Differential Interferometry Synthetic Aperture Radar), the computer numerical modeling method, the Finite Element Analysis (FEA) and the remote computing technology. First, the pre- and co-seismic deformation of Mani Ms7.9 Earthquake is acquired using D-InSAR technique. In order to gain some new knowledge about the medium mechanical parameters of the south and north walls of the Mani earthquake fault, the pre-seismic deformation field was simulated using FEA software. Based on Okada elastic half space dislocation theory, a tele-computing system is developed, which can simulate the co-seismic D-InSAR interferometry deformation field at any Internet terminator. As a study example of using this new system, this work tele-simulates the co-seismic deformation field of the Mani earthquake and attains part of the geometrical and kinematical parameters of this strong earthquake. On the basis of previous studies, this work gains some new conclusions described below.①Using D-InSAR technology, the co-seismic deformation field of the Mani Ms7.9 earthquake is obtained.The Mani Ms 7.9 earthquake happened at the north border of the Qiangtan basin of Tibet, near the NEE trending Maergaichaka-Ruolacuo fault, on 8 November 1997. The region of Qiangtan, which means a place where nobody lives in the language of Tibetan, has cold weather and thin air. Because of its hard field conditions, there is no deformation observation station around several hundreds kilometers in circuit. All these realistic situations put limits on learning the surface deformation field of the earthquake region and deformation of active faults. Fortunately, D-InSAR technology is available which is not affected by all these factors and has preponderant advantages in acquiring information of spatial deformation field evolution.This work collected 16 wells ERS-1/2 Radar Satellite data of European Spatial Bureau from January 1995 to December 2000. Two ERS-1 SAR data are included: 2889/19960415, 2907 /19960415. And there are 14 ERS-2 SAR data: 2889/19960416, 2907/19960416, 2889/19970121, 2907/19970121, 2889/19970610, 2907/19970610, 2889/19970819, 2907/19970819, 2889/19971202, 2907/19971202, 2889/19980421, 2907/19980421, 2889/19990406 and 2907/19990406. These SAR data are handled using three-pass Differential Interferomertry mode.更多还原