Application of SBAS-InSAR for monitoring geothermal-induced ground deformation in the Munich Region

This study demonstrates the capability of the Small Baseline Subset (SBAS-InSAR) technique to resolve low-magnitude surface deformation in regions prone to high spatial and temporal decorrelation. By processing Sentinel-1 data (October 2020–June 2023) at dual resolutions of 80 m and 160 m for the Munich geothermal region, we resolved vertical and horizontal displacement rates of up to ±2 mm/year. The rates are low compared to many geophysical signals, but they are clearly resolvable with SBAS-InSAR. This demonstrates the technique's utility for monitoring complex environments such as urban infrastructures. The results are evaluated through comparison with external data obtained using the PS-InSAR technique.

In the Munich region, geothermal operations have previously triggered minor seismic events, such as in Unterhaching and Poing. We aim to study if non-linear stress changes that precede seismic failure can be identified in the time series and isolated from other processes, such as construction works (e.g., the new railway line), as well as other geophysical processes like hydrology. Subtle velocity gradients could serve as critical indicators of subsurface stress accumulation and provide an important empirical basis for validating geomechanical models and ensuring the long-term safety of geothermal energy expansion.