Measurements of U and Ra in100 soil samples collected from Gejiu area in Yunnan Province show that the Ra/Uequilibrium ratio is 0.65,implying that Uis richer than Ra.Some indications of regional disequilibrium have also been found.The spreading equilibrium ratio values indicate that disequilibrium may cause errors in Uchannel data obtained by ground gamma-ray surveying. Neverthelsss,these data can be improved to some extent by equilibrium ratio correction.
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