Measuring Land Deformation Through PSI Technique in NE Sardinia (Italy): Roads to Einstein Telescope

The Einstein Telescope (ET) is a proposed underground infrastructure to host a third-generation, gravitational-wave observatory. Currently, two European candidate-sites are competing to host it: one is located in the area of Sos Enattos in Northern Sardinia (Italy), probably in the most favourable geological context, the second is in the Meuse-Rhine Euregion. The choice of the most suitable site to host this new unique research infrastructure will be decided by an international commission, considering the feasibility of the construction and predicting the impact of the local environment on the detector sensitivity and operation. This site-characterization analyses are under way and the final decision is expected by the end of 2024. The present study is part of the geological characterization of the site of Sos Enattos, and is focused on the evaluation of the surface deformations of its area by means of Synthetic Aperture Radar (SAR) data. In this framework, the PSI (Persistent Scattered Interferometry) technique with SAR data provided by Sentinel-1 mission is the proposed approach for the analysis of a long time-series imagery. Time-series of data were processed, exploiting the complete Sentinel revisiting time, starting from 2014 to October 2022. The first results of this analysis have been processed using the existing GNSS measures provided by EUREF network as reference and the ground vertical displacement has been calculated after decomposition of LOS velocities. In this work, the results of ground vertical displacement calculations for the study area are described, and particular study-cases are discussed. The first results of this study confirm the very low values of vertical displacements in the area, as confirmed by the known geological setting. These results can be considered an important value for the proposed Italian site and the ET infrastructure realization