Ground deformation retrieval of urban and suburb areas based on multi-baseline DInSAR algorithm: A case study in Cangzhou City (China)

This paper aims at ground surface deformation retrieval in wide areas including urban and suburb areas based on multi-baseline DInSAR algorithm proposed by Mora. Several progresses are made in order to extract good results. Firstly, a new complex network is presented to restrain noise influence on delaunay triangular network. Secondly, Based on a model coherence function, linear deformation velocity increments and height error increments between neighboring high coherent points (HCPs) are resolved. In order to integrate increments in network, least squares adjustment method and error controlling method are used to obtain stable parameters estimation. At last, by Combining complex and delaunay networks, wide areas deformation is investigated, from center urban areas to suburb areas. The algorithm is performed to investigate the subsidence of CangZhou City, Hebei province (China) during the time of 1993-1997 by using 9 scenes of ERS SAR data. The experiment results show serious subsidence in the region and are validated by leveling data and groundwater wells data.