A preliminary study on soil radon anomaly and its formation mechanism in karst area of southwest China

Soil radon anomaly is a common phenomenon in karst areas. In this paper, the geochemical behavior of radium (Ra) in the process of carbonate rock weathering and soil formation was used to reveal the accumulation mechanism of soil radon. In the karst area and non-karst area, 24 soil points were collected to measure radon and radium, and a carbonate weathering profile was collected in the karst area. The research showed that: (1) the theoretical radon value obtained from Ra is far greater than the radon value measured on site, indicating that soil Ra can provide a potential source for the source of soil Rn; (2) through the study of the geochemical behavior of Ra during the weathering process, it was found that Ra was significantly enriched during carbonate weathering. This paper deepened the understanding of the geochemical behavior of radionuclides (Ra, Rn) in karst environments. (author)