Abstract We propose a method to identify the development mechanism of debris flow by combining the phase information and backscatter information of SAR image, so as to explore the substance source collection and instability mode of debris flow in Yizhong river of Dêqên county, Yunnan province. The spatial-temporal variation trend of soil moisture in the study area is inversed by backscatter coefficient, and the two-dimensional deformation of slope surface is obtained by using ascending and descending orbit sentinel-1A data. The results show that the soil moisture and surface deformation in the study area show periodicity and strong correlation, and the early source collection is affected by the dry-wet cycle. The soil moisture increases from January to June, and the surface soil expands under the action of high pore pressure. The surface material source is stripped and transported downward, affected by wind from July to December, supplying material source for the debris flow forming area. Using SBAS-InSAR to obtain the time series deformation of the surface reveals that the soil is unstable due to drought at the beginning of the year, later activated by rainstorm scouring. The method we propose provides a new idea for InSAR technology in the interpretation of debris flow development mechanism and has the function of early warning and prediction for debris flow disasters.
CHEN Tingxuan,LI Sumin,YUAN Liwei. InSAR Study on Substance Source Collection and Instability Mode of Yizhong River Debris Flow in Deqin, Yunnan Province[J]. jgg, 2022, 42(2): 158-164.
CHEN Tingxuan,LI Sumin,YUAN Liwei. InSAR Study on Substance Source Collection and Instability Mode of Yizhong River Debris Flow in Deqin, Yunnan Province[J]. jgg, 2022, 42(2): 158-164.
