A Study on the Detection of Deformation of Tuotuohe Area on the Qinghai-Tibet Plateau

Abstract

In permafrost regions, the ground surface deformation is closely related to the ice-water phase transition process in active layer and underground ice. It is of great significance to carry out ground surface deformation detection research for understanding the development of permafrost in the Qinghai- Tibet Plateau. The InSAR technology has been proved to be an effective method for monitoring frozen soil deformation. However, due to the limitation of spatial coverage and revisit cycle of SAR data, few scholars had paid attention on the unstable permafrost regions with less ice content in the previous studies. Thus, a less ice content permafrost region loceted in Tuotuohe was taken as the study area to carry out surface deformation detection research based on SBAS-InSAR technology, and the field measurement was carried out to do the verification. The result showed that there was a good agreement between them, and the errors are 0.9mm, 2.6mm and 2.8mm respectively. The deformation detected by SBAS-InSAR method well reflects the frost heaving and thaw subsidence trend along with seasonal changes. Considering the small content of underground ice, this trend mainly reflects the seasonal freezing-thawing variation of the active layer. This study further confirms the applicability of InSAR technology in unstable permafrost regions.