星载SAR遥感山区滑坡隐患识别与三维监测方法研究

Landslides in mountainous areas generally have characteristics of concealment and paroxysm. This increases the difficulties of landslide prevention and early warnings. With development of new synthetic aperture radar (SAR) satellites and SAR image processing algorithms, the great potential of Spaceborne SAR in landslides monitoring have drawn great attentions. However, limited by the variations of landslides slopes, aspects, displacement rates and the SAR side-looking observation geometry, there are still crucial unsolved problems in aspects of potential landslide detection and accurate landslide displacement measurement. Therefore, this project will be carried out following the main line of "potential landslide detection –accurate landslide displacements monitoring – time series three dimensional displacements inversion". We will firstly develop an approach to identify potential landslide in mountainous areas with multi-track SAR datasets. Then, multi-temporal InSAR and pixel offset tracking method by jointly using persistent scatterers and distributed scatterers will be developed to accurately measure landslides displacement in SAR geometry. Afterwards, we will explore time series three dimensional displacements inversion method from multi-track SAR measurements. Finally, a methodological framework for mountainous landslide stability monitoring with Spaceborne SAR remote sensing will be established. The proposed methods of this project will improve the geohazards monitoring ability of radar remote sensing in mountainous area, and provide reliable measurements for disasters prevention and hazard management.

山区滑坡的隐蔽性和突发性特点，大大增加了滑坡灾害的危险性和防范难度。随着星载合成孔径雷达（SAR）系统和SAR数据处理算法的发展，星载雷达遥感在山区滑坡灾害形变监测方面的优势日益突出。然而由于山区滑坡坡度坡向以及形变速率的差异和SAR侧视成像几何的限制，现有方法在滑坡隐患识别和滑坡形变信息精确提取等方面还存在问题亟待解决。为此，本项目以“滑坡隐患识别——滑坡形变提取——滑坡时序三维形变反演”为主线，首先发展星载SAR数据滑坡隐患识别方法，在此基础上，研究结合点目标和分布式目标的InSAR时序分析和像素偏移量分析等形变监测方法，精确获取滑坡表面形变，进而提出结合多轨SAR数据时序观测获取滑坡表面时序三维形变的新方法，最终构建星载SAR山区滑坡形变识别监测方法技术体系。本项目研究成果有望明显提高星载雷达遥感山区地质灾害变形监测能力，为减灾防灾以及灾害管理决策等提供可靠依据。

近年来，我国西部山区灾难性地质灾害频发，给我国的国民经济安全生产带来了很大的威胁。而滑坡的隐蔽性和突发性特点，大大增加了滑坡灾害的危险性和防范难度。得益于星载SAR遥感的大范围覆盖和形变监测能力，InSAR技术在山区滑坡灾害形变普查方面发挥着越来越重要的作用。本课题研究了联合永久散射体和分布式散射体的时序InSAR测量的方法提取缓慢地质灾害变形；研究了基于点目标的方位向和距离向时序子孔径干涉测量技术提取快速变形；研究了基于三次样条曲线多轨道数据地表时序三维变形提取方法。本项目研究成果已经在我国受地质灾害影响较为严重的三峡库区、青海、山西等地区取得成功应用，可为防灾减灾提供有力支撑。