GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 1.1 GNGTS 2023 Monitoring of the hydrologically-induced crustal variations in the Altotiberina-fault zone (Northern Apennines, Italy) C. Almagro Vidal, F. Pintori, L. Zaccarelli, E. Serpelloni Introduction The monitoring of changes in the Earth’s crust is a fundamental process carried out with various geophysical methods. In the study of crustal perturbations originating in depth, the identification of the cause of perturbation and quantification of its effect can be affected by additional sources related to climatic/atmospheric phenomena. In some particular cases, these phenomena can dominate the crustal changes and its effects extend down to significant depth. Therefore, geophysical measurements aiming to study the evolution of both crust deformation and perturbation of its mechanical properties due to deep phenomena can in many cases be biased by climate seasonality and a proper analysis of the effect of this phenomena is essential. The ‘Altotiberina Near Fault Observatory’ serves the purpose of monitoring ground deformation, crustal perturbations and seismicity in the homonymous fault zone through a multidisciplinary infrastructure comprising seismological, geodetic, and geochemical measurements (Chiaraluce et al., 2014). Given the strong impact that water variations can induce onto the ground, the geophysical monitoring in the Altotiberina fault (ATF, see Fig.1) zone requires accurate identification and quantification of the hydrologically-induced crustal perturbations in this research area. In this work we identify and monitor hydrologically-induced crustal perturbations at the ATF zone over a 12-year long period. The results are obtained from geodetic observations with a GNSS network of 33 stations, and seismic observations with a network of 45 stations. These observations are confronted with a hydrological mass-balance model estimate based on meteo-climatical observations over a restricted control area defined by the Tiber upper basin watershed (see Fig.1).