PS-InSAR monitoring and finite element simulation of geomechanical and hydrogeological responses in sedimentary formations

With the first use of the corner reflector based permanent scatterer interferometric synthetic aperture radar (CR-PS-InSAR) technology, the earth´s surface deformation, strongly associated with subsurface flow, of Horonobe underground research laboratory (URL) is successfully monitored during its construction. The temporal and spatial characteristics of interferometric signatures collected from CR point targets are exploited to accurately map surface deformation histories and terrain heights of the URL site, especially around the monitoring boreholes. By developing a hydromechanical poroelastic model, satellite monitoring is linked to characterization of deep groundwater flow. The geomechanical and hydrogeological responses of sedimentary formations to the drilling of the shaft was modeled using a two-dimensional finite element model. A good correlation between measured and modeled responses indicated that both the boundary conditions and rock properties are well understood by the proposed coupled inversion methodology.