Detection of mining related ground instabilities using the permanent scatterers technique - a case study in the east of France

Ground stability is a major concern for land use planning and both natural and anthropogenic risk assessment, especially in urbanized areas. Space-borne differential radar interferometry provides a unique tool able to give a synoptic view of ground deformation with centimetric to millimetric vertical precision. Approaches for combining a wide range of radar images such as the permanent scatterers (PS) technique allow the estimation of the deformation history of single buildings. The PS approach has been exploited to investigate a test site particularly exposed to ground deformation hazards, namely the iron mining basin in Lorraine (France). In this Letter, a specific focus was set on the case of Roncourt, where precursor signs of a collapse affecting an area of similar to300 x 300 m(2) have been identified.