Soil radon flux fluctuation near the ground surface:Relationship with heavy precipitation

We are developing underground and atmospheric radon observations using an α-ray detector in Chiba-Ibaraki to investigate the relationship between earthquakes and radon emissions from the ground. In this paper, we investigated the relationship between soil radon flux (SRF) and heavy precipitation, and found that SRF was significantly increased by heavy precipitation of 20 mm or more in total for 2 hours. We proposed two types of models, a rainwater load model and a rainwater infiltration model, and it is appropriate for both models to work.