Font Size: a A A

Ground Subsidence Monitoring In Mining Area Using InSAR

Posted on:2010-07-31Degree:MasterType:Thesis
Country:ChinaCandidate:H J YinFull Text:PDF
GTID:2120360305993149Subject:Geodesy and Survey Engineering
Abstract/Summary:PDF Full Text Request
The excess exploitation of underground natural resources often causes degradation of geological environment and geological crisis, such as persistent land subsidence of mining areas, ground fissures, landslide and debris flow, etc. Subsidence associated with abandoned mines can pose great threats to life and property of people. Interferometric Synthetic Aperture Radar (InSAR) has been demonstrated to be an important remote sensing tool for the estimation of temporal and spatial surface motions due to ground subsidence with the accuracy of subcentimetre over last decade. In this paper, we first present a new InSAR phase filtering method based on optimal integration. Then a case study of Lengshuijiang mining area of Hunan Province with the application of Differential InSAR (DInSAR) and Small Baseline Subset (SBAS) algorithm is conducted.The study is focused on the approach of ground subsidence mornitoring using InSAR technology. Aiming at surpressing strong phase noise of interferogram of mining areas, we develop a new InSAR phase filtering method based on optimal integration. The algorithms can preserve very well the phase details while smoothing out the noise, thus the accuracy of deformation monitoring with InSAR is improved. With the case of lack of enough SAR images acquired in the study area, we use Small Baseline Subset (SBAS) DInSAR algorithm to monitor the temporal evolution of surface deformation in mining area. The main research work includes:Firstly, we develop a new InSAR phase filtering method based on optimal integration. The proposed filter is adaptively implemented by altering the number of the linear windows selected for filtering. Coherence is chosen as parameter to determine the number of the linear filtering windows. Optimal integration is used to combine the selected directional windows. The new filter considers the local statistic characteristic of the interferogram and can be implemented adaptively by the introduction of coherence. Experimental results with both simulated and real data sets of L-band show that the filter proposed in this paper can filter out noise efficiently and cause almost no blurring and phase distortion to the interferometric fringes.Secondly, the deformation maps of Lengshuijiang mining area of Hunan Province for different time period are derived using L band PALSAR data and traditional DInSAR method.Finally, a temporal deformation sequence of Lengshuijiang mining area of Hunan Province is retrieved from DInSAR phase based on virtual observation method and SBAS algorithms. The retrieved deformation sequence of Lengshuijiang matches very well with the exploitation process.
Keywords/Search Tags:InSAR, subsidence of mining area, deformation monitoring, phase filtering, small baseline subset, time series analysis
PDF Full Text Request
Related items