Ground Fracturation in Urban Area: Monitoring of Land Subsidence Controlled by Buried Faults with InSAR Techniques (Ciudad Guzman: Mexico)

On September 21st, 2012 Ciudad Guzman (Jalisco-Mexico) was struck by an intense linear ground fracturation, causing deformations of roads and serious damages to some houses. In order to highlight any precursor deformation pattern in the area we applied InSAR multi-temporal analysis to process a dataset of ENVISAT satellite SAR images, acquired in 2003-2010 time span. We detected a subsidence area in the north-western part of Ciudad Guzman up to -20 mm/y in the considered time interval. The eastern boundary of this area is coincident with the September 2012 alignment of fractures. The explanation of subsidence and surface effects, based on the interferometric results, ground data and geological observations, is probably to be found in the combination of two mechanisms such as overexploitation of the aquifers and tectonic creeping. In summary, the deformation pattern highlights a natural subsidence enforced by anthropogenic causes with the control of buried faults.