Surface deformation analysis of Xian (China) in 2009 carried out with refined SBAS-DInSAR

Taking the land subsidence and ground fissure in Xian as the research object and nine Envisat ASAR images spanning the whole year of 2009 as the data source, time series surface deformation of Xian city from January to December in 2009 are obtained by SBAS-DInSAR approach, where the baselines and topographic phase were refined using ground control points (GCP). The results show that Xian is the state of continuous subsidence in 2009 and subsidence funnels are shaped nearly in oval whose long axis direction was approximately parallel to ground fissure direction. Meanwhile, the regional and seasonal characteristics were displayed for these subsidences regional. In addition, spatial distribution of strong activities and active regulation within the year between ground fissures and land subsidence are uniform based on this investigation.