Tectonically induced signals recorded in Italy by geochemical and hydrogeological methods

Crustal deformative processes are usually monitored by GPS or by satellite-based techniques. Significant signals have been recorded in many places of the world after strong earthquakes. Only in a few cases similar signals were detected before seismic events due to the relatively low sensitivity of equipments (Roeloffs, 2006; Cicerone et al., 2009). Due to the about non compressible character of water and to deep origin of CO2, deep originated fluid monitoring could be more sensitive in revealing weak signals related to crustal deformations and contribute to earthquake precursors researches (Martinelli and Albarello, 1997; Martinelli and Dadomo, 2017). Recorded data do not show significant dependence to meteorological or artificial parameters. Part of the observed signals have been detected before mainshocks and could be related to aseismic slip (e.g. Johnston and Linde (2002) or to seismic slip eventually induced by fluctuations in minor seismicity. Earthquake forecasting researches could benefit by the joint utilization of different monitoring techniques applied to geofluids.