Methodology for Detection and Interpretation of Ground Motion Areas with the A-DInSAR Time Series Analysis

Recent improvement to Advanced Differential Interferometric SAR (A-DInSAR) time
series quality enhances the knowledge of various geohazards. Ground motion studies need an
appropriate methodology to exploit the great potential contained in the A-DInSAR time series.
Here, we propose a methodology to analyze multi-sensors and multi-temporal A-DInSAR data for
the geological interpretation of areas affected by land subsidence/uplift and seasonal movements.
The methodology was applied in the plain area of the Oltrepo Pavese (Po Plain, Italy) using ERS-1/2
and Radarsat data, processed using the SqueeSAR™algorithm, and covering time spans, respectively,
from 1992 to 2000 and from 2003 to 2010. The test area is a representative site of the Po Plain, affected
by various geohazards and characterized by moderate rates of motion, ranging from 10 to 4 mm/yr.
Different components of motion were recognized: linear, non-linear, and seasonal deformational
behaviors. Natural and man-induced processes were identified such as swelling/shrinkage of clayey
soils, land subsidence due to load of new buildings, moderate tectonic uplift, and seasonal ground
motion due to seasonal groundwater level variations.