光学遥感影像阴影与2008年汶川地震同震地表变形的影像识别

INTERPRETATIONAL CHARACTERISTICS OF OPTICAL REMOTE SENSING IMAGE FOR THE CO-SEISMIC SURFACE DEFORMATION OF THE 2008 WENCHUAN EARTHQUAKE AND ITS RELATIONSHIP WITH IMAGING

遥感影像数据在2008年汶川地震抗震救灾和灾后恢复重建中发挥了重要的作用,充分利用遥感技术进行同震地表变形的快速识别与地震地质研究具有重要的现实意义。通过分析震后光学遥感影像的阴影、纹理等特征,以及野外获得的地表破裂变形的地质与地貌特征,总结了汶川地震同震地表变形的光学遥感影像识别特点。从遥感成像的光学原理深入解析了汶川地震断层陡坎在遥感影像上的阴影形成与识别特征,明确了成像时刻和断坎产状对影像阴影的形成和断层陡坎识别能力的约束。结合影像成像特征与汶川地震同震地表破裂特征的应用分析,客观地认识了现有遥感影像在同震地表变形应用中的局限性,可为今后的应急航空遥感方案设计提供参考。

Data from remote sensing played important roles in the rescue during the 2008 Wenchuan earthquake and reconstruction after the great disaster. It also has much realistic significance to implement a rapid interpretation and geological study from those data. Analysis was made on the characteristics of optical remote sensing image, such as shadows and texture, and geological and geomorphological features of the surface rupture from field investigation. The interpretation marks of the post-earthquake optical remote sensing image were concluded for the fault scarp of the great Wenchuan earthquake. Based on the optical imaging, the shadow forming and interpretation characteristics of different kinds of fault scarp were analyzed for the Wenchuan earthquake. The imaging time and the occurrence of fault scarps make a constraint on the forming of shadows and its interpretation for fault scarps. Analysis based on characteristics of imaging and rupture styles gives a new insight on the limitation in the application of remote sensing data of co-seismic surface deformation,and also a certain proposal for the emergency aerial remote sensing in the future.