Abstract
<jats:p>The Starobin potash salt deposit has been mined for over forty years with annual extraction measured in millions of tons. In the vicinity of tectonic fault junction zones, this creates a risk of local technogenic earthquakes caused by fault activation. Local geodetic monitoring within mining allotments is of limited utility for assessing large-scale tectonic deformations, since intense local technogenic subsidence masks the regional signal. Deploying a dense GPS network is economically and technically challenging. In this study, we test the applicability of Persistent Scatterer Interferometry (PSI) on Sentinel-1 data for large-scale geomechanical monitoring of fault zones. Processing was carried out on a stack of 12 SAR scenes (December 2020 -- November 2021) using the SNAP--StaMPS environment for both ascending and descending tracks. Raw StaMPS LOS velocities in the Tanezhitsy/Chaplitsy area amounted to ~30 mm/yr (ascending) and ~10 mm/yr (descending). Verification against two GPS reference stations on the northern fault block (~5 mm/yr, southwest) revealed a systematic overestimation of LOS velocities in the SNAP--StaMPS pipeline with a scaling factor K_scale ~ 11.5. A favorable circumstance — the near-collinear alignment of the ascending scan beam direction with the block displacement direction — enabled a simplified multiplicative calibration without full 3D decomposition. After calibration, corrected LOS velocities (2.6 mm/yr) are by construction consistent with the GPS reference. It is shown that, for the conditions of the Starobin deposit, the ascending and descending tracks exhibit different sensitivity to horizontal and vertical deformation components: the ascending track detects predominantly tectonic horizontal displacement, while the descending track captures vertical technogenic deformations. The geological interpretation indicates a strike-slip zone with a vertical component. Additionally, critical displacement zones of infrastructure objects were identified.</jats:p>