Long-distance migration of radon within the earth

There is need for identification and understanding of methods for locating subsurface uranium. A major hope for definitive recognition of ore at depths of more than a few meters is the measurement of the near surface emanation of 222Rn, the sole distinctive gaseous product of the decay of uranium. Scattered observations suggest that radon can migrate through the earth for distances of greater than or equal to 100 m. A model is proposed in which convective flow of subsurface air or water through a porous medium is induced by the geothermal gradient. Several of the predictions of the model are consistent with observations at a uranium ore deposit in New Mexico