Surface deformation induced by water influx in the abandoned coal mines in Limburg, The Netherlands observed by satellite radar interferometry

The coal reserves of Limburg, The Netherlands, have been exploited until the mid-1970's, leading to significant land subsidence, a large part of which was due to ground water pumping associated with the mining activities. In 1994, when also the hydrologically-connected neighboring German mining activities ceased, all pumps were finally dismantled. This resulted in rising groundwater levels in the mining areas, continuing until today. Here we report the detection and analysis of heterogeneous surface displacements in the area using satellite radar interferometry. The lack of adequate terrestrial geodetic measurements emphasizes the value of such satellite observations, especially in terms of the temporal and spatial characterization of the signal. Since the lack of direct mine water level measurements hampers predictions on future consequences at the surface, we study the relationship between surface deformation and sub-surface water levels in an attempt to provide rough correlation estimates and map the mine water dynamics.

► We study surface displacements in abandoned mines with InSAR time series analysis. ► We examine the relationship of these displacements with mine water levels. ► We find high correlation between water levels and surface displacements. ► Rising water levels produces surface uplift. ► We model rock dilatation caused by pore pressure increase due to rising mine waters.