SAR相干点多层次联合监测断裂带震间微小形变研究

This project studies combination of the three kinds of SAR coherence points, which contain CR(Corner Reflector)，PS (Permanent Scatterers)，DS(Distributed Scatterer), to monitor micro interseismic deformation of the Haiyuan fault，west Qinling fault and Liupanshan fault in northeastern margin of Tibet Plateau. The contents are as follows: Firstly, we analyze intensity and phase of the CR point in time series, which is of high precision and stability. Secondly, A algorithm selecting high-quality coherent point is proposed，based on the intensity and phase time series feature of CR point. Thirdly, finding out a method to remove the atmospheric phase of coherent point, we also study method of network construction of coherent point and model of interseismic deformation calculation. Finally, in order to get a large scale, wide coverage, high density result of micro interseismic deformation in the target fault zone, a third-level deformation monitoring network is established by combining CR, PS and DS point. And we improve the precision of deformation calculation of PS, DS point through the high precision CR point.This research aims to provide a scientific basis for understanding current deformation of these three faults in detail.

本项目以CR(Corner Reflector)、PS (Permanent Scatterers)、DS(Distributed Scatterer)三种不同类型SAR相干点为对象，研究CR、PS、DS点联合解算方法监测青藏高原东北缘海原、西秦岭北缘、六盘山断裂震间微小形变。具体内容包括：分析高精度、高稳定性CR点的强度、相位时序特征；以CR点时序特征为参考先验信息，提出高质量PS点选取算法；建立相干点大气相位校正模型；研究相干点间构网方式及震间形变解算方法，最后将CR、PS、DS点联合建立三级形变监测网，为提高形变监测精度以CR控制PS、DS点形变解算，最终获取面积大、覆盖广、点位密度高的震间微小形变结果，为详尽认识这三条断裂现今活动提供科学依据。

本项目以利用InSAR相干点CR(Corner Reflector)、PS(Permanent Scatterers)、DS(Distributed Scatterer)联合监测断裂带震间形变为目标。基于三种不同类型相干点（CR、PS、DS）特征，研究CR、PS、DS点联合构网解算监测青藏高原东北缘海原、西秦岭北缘断裂震间微小形变。具体研究内容包括：分析了角反射器（CR）的强度、相位值及时序特征，得CR具有高强度、时序相位稳定特征；基于CR时序相位稳定特征，结合强度离差指数阈值法提出了高质量PS点选取新算法；研究了相干点大气相位校正方法；设计了相干点间不同层级的构网方式及震间微小形变解算过程；利用CR、PS、DS点逐级联合建立了一级、二级、三级形变监测网，监测断裂带震间微小形变，对不同层级监测结果具体量化分析，对比分析、总结了不同联合监测手段的技术特点及适用条件。基于形变监测结果采用震间位错模型反演了断裂深部滑动速率、闭锁深度。本项目成果为研究区断裂活动提供数据支持，为InSAR监测断裂震间微小形变提供理论与技术支撑。