Resumen de Use of PSInSAR data to map highly compressible soil layers.

C. Del Ventisette, L. Solari, F. Raspini, A. Ciampalini, F. Di Traglia, M. Moscatelli, A. Pagliaroli, S. Moretti

• A new approach for the use of PSI (Persistent Scatterers Interferometry) data in the reconstruction of extension of compressible geological bodies is presented. The methodology was applied in the test area of the Tiber river delta (Italy), characterized by the presence of two large marshy zones, known as Maccarese and Ostia Antica ponds. PSInSAR™ data, derived from ERS1/2, ENVISAT and RADARSAT-1 images, were used to verify the possibility to reconstruct, starting from boreholes information, the spatial distribution of the peat levels inside the Maccarese and Ostia Antica ponds. The boreholes were analyzed to calibrate the InSAR data; therefore the deformation rates were used to hypothesize the presence of a thick compressible layer where geological information is lacking. Variations in deformation rates registered by the single PS were assumed to be representative of a variation in the stratigraphic asset. The obtained results demonstrate that this approach could be satisfactorily used to investigate wide areas in a short time, limiting the numbers of boreholes to drill, and it could be a complementary technique to obtain information about the 2D geometry of specific geological levels.