导　　师： 伍吉仓

学科专业： 081601

授予学位： 硕士

作　　者： ;

机构地区： 同济大学

摘　　要： 在过去的15年间，INSAR作为一种相对较新的遥感技术已被广泛应用于与地震、火山、滑坡、沉降相关的形变研究领域。LNSAR用于地震形变研究的主要优点是空间分辨率率高、成木较低。另外SAR数据覆盖了全球大部分区域，这对那些发生于无常规测地数据区域的地震尤为重要。本文致力于深化对INSAR技术原理的理解和探索INSAR在地震形变观测领域的应用。 在传统高程模型的基础上，本文提山一种改进的INSAR高程模型，建立了高程和干涉相位的直接关系，并对公式推导中一般采用的平行射线近似处理方法所引入的高程误差进行了量化分析并给出了近似误差与基线参数的确定性关系及相应的误差传播曲线。结果表明，对于星载雷达而言，平行射线近似误差不能忽略。本文还推导了一种兼顾参考相位的高程模型，在不作近似假设的情况下，推导出的公式与基于近似假设的公式一致，证明了去平地效应环节除了能消除参考相位还能有效消除平行近似误差。 接着，本文分析了SAR回波信号的构成及干涉相位的统计特性，系统研究了经多视处理后SAR干涉相位的概率密度函数与相干系数、视数的关系，明确了在不同视数下，噪声对干涉图质量的影响，为干涉图的质量评价和误差消除提供了理论依据。 在DORIS平台上利用三轨差分方法处理了台湾集集地震前后获取的SAR数据，并分析了干涉图中存在的误差。利用GPS观测数据对轨道误差进行了纠J下，最终得到的同震位移场与GPS数据有着很好的一致性。 集集地震使得车龙辅断层面出现了明显滑移。本文利用1068个三角形单元重新构建了车龙辅断层几何，基于角位错理论反演了断层的滑移量分布。与矩形位错单元相比，三角形单元的反演结果与实际数据更为相符。通过对GPS和INSAR数据的联合反演，发现了在断层滑脱面上有明显滑移，证实了在颇具争议的车龙辅断层几何上应该存在滑脱面。 During the last 15 years, InSAR as a relatively new remote sensing technique has been widely used to study the displacement related to earthquake, volcanoes, landslides, oilfields and mines. The main advantages of InSAR for studying seismic deformation are the low cost and high spatial resolution. In addition, the available SAR data covers most subaerial areas in the world. This is particularly important because many earthquakes occur in areas where no conventional geodetic measurements exist. The work is dedicated to the understanding of the principles of InSAR and its application to the study of displacements caused by earthquake. Based on the traditional InSAR elevation model, I develop an improved one which expresses the direct relationship between height and phase. In this model and other available InSAR models, the parallel ray approximation or far-field approximation is widely used. I analyze the errors introduced by the parallel ray approximation and conclude that it can not be ignored for elevation determination through satellite radar system. Meanwhile, I also derive a formula of flattened interferometric phase which verifies that the approximation error can be canceled by removing the contribution to the interferometric phase due to the reference surface. I analyze the statistic characteristics of SAR signals and interferometric phases and the relation between PDF and coherence and multilook numbers which reflects the impact of noise to interferogram under different multilook. The result is help to assess the quality of interferogram and eliminate errors. In the work, I attempt the differential interferometry using 3 ERS-2 C-band images, which were acquired over the tectonically active area of Taiwan where the 1999 Chi-Chi earthquake accured. The errors existed in the interferogram were analyzed and the orbit residual is removed by GPS observations. The slip of the Chelungpu fault triggered of the Chi-Chi Taiwan earthquake /(Mw=7.6/) which caused a 100-km-long surface rupture that trends north-south. I reconstruct the fault geometry using 1068 planar triangular dislocation elements which better approximate the realistic curved three-dimensional fault surfaces and perform the slip inversion with the observed GPS coseismic displacements as well as InSAR data. The inverting results show that smooth 3D fault model has improved the fit to the geodetic data. By combined inversion of the GPS and InSAR data, we find

关 键 词： 地震形变 集集地震 位移场 滑移量反演 数据处理 台湾

分 类 号： [P315.63]

领　　域： [天文地球] [天文地球] [天文地球]