Detecting subsidence-induced faulting in Mexican urban areas by means of Persistent Scatterer Interferometry and subsidence horizontal gradient mapping

We present a subsidence study based on the analysis of displacement measurements from ENVISAT-ASAR Persistent Scatterer Interferometry and on the extraction of horizontal gradient maps. Land subsidence is analyzed for three cities in central Mexico: Chalco, Aguascalientes and Morelia. Even though stratigraphic and tectonic backgrounds of these areas impose different subsidence patterns as imaged through the interferometric analysis, the three case studies all reveal the necessity of a combined analysis of subsidence magnitudes and horizontal gradients for better definition of the areas with higher vulnerability to surface faulting. Such an analysis can be used as the basis for subsequent hazard and risk mapping.