Natural radionuclides in rocks, water, and organic matter are commonly used as tracers for studying geological and hydrological cycles, including groundwater movement. One of the most characteristic and successful applications of radioactivity in earth sciences is its use as a natural “clock” measuring successively processes, from minutes to billions of years, occurring on the Earth. In the framework of the multidisciplinary INGV-PROMUD research project, aimed at identifying key indicators of mu