Radon in groundwaters from Guarany aquifer, South America: environmental and exploration implications

Groundwater and sandstone samples were analyzed for radon in Guarany aquifer, Paraná sedimentary basin, South America. The dissolved radon ranged between 3 and 3303 pCi/l, being lognormally distributed, with a modal value of 1315 pCi/l, and a median value of 330 pCi/l. 222Rn leakage experiments for sandstones yielded a theoretical value of 1390 pCi/l for 222Rn in water, showing that theoretical modeling can reliably be used to interpret laboratory and field data.