Ground Deformation Associated With Post-Mining Activity at the French-German Border Revealed by Multidimensional Time Series Analysis of SAR Data Acquired in Various Orbital Geometries
Abstract
We present the application of an innovative methodology for producing multidimensional time series of ground deformation from satellite radar data acquired by sensors with various acquisition geometry, ground resolution, and wave band (Samsonov and d'Oreye, Resubmitted). This technique is based on the Small Baseline Subset (SBAS) method that is modified to produce horizontal and vertical time series of ground deformation. Produced time series have combined coverage, improved temporal resolution and lower noise level. We apply this methodology for mapping coal mining related ground subsidence and heave in the Greater Region of Luxembourg along the French-German border. For this we processed 167 Synthetic Aperture Radar ERS-1/2 and ENVISAT images acquired between 1995 and 2009 from one ascending (track 29) and one descending (track 337) tracks and created over five hundred interferograms that were used for time series analysis. Produced vertical and east-west linear deformation rates show with remarkable precision region of localized ground deformation located above and caused by mining and post-mining activities. Time series of ground de- formation display temporal variability: reversal from subsidence to uplift and acceleration of subsidence on the vertical component and horizontal motion towards the center of the subsidence on the east-west component. InSAR results are successfully validated by leveling measurements performed by the French Geological Survey (BRGM) during 2006-2008. We determined that deformation rate changes are mainly caused by water level variations in the mines. Due to higher temporal and spatial resolution the proposed space-born method detected a larger number of subsidence and uplift areas in comparison to leveling measurements restricted to annual monitoring of benchmark points along roads. We also identified deformation regions that are not precisely located above the mining sites. Comparison of InSAR measurements with the water levels measured in the mining pits suggest that part of the water that invaded the galleries after termination of the dewatering systems may come from these regions. Providing that enough SAR data is available, this method opens new opportunities for detecting and locating man-made and natural ground deformation signals with high temporal resolution and precision.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.H24C..02S
- Keywords:
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- 1211 GEODESY AND GRAVITY / Non-tectonic deformation;
- 1803 HYDROLOGY / Anthropogenic effects;
- 9335 GEOGRAPHIC LOCATION / Europe