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对采自全澳大利亚445个土壤样品中铀和镭的测量表明,土壤中铀的平均含量为2.0×10~(-6),U/~(226)Ra的活度比为1.09。虽然单个样品值的变化范围很宽,但总体上富铀土壤多于富镭土壤。Cross-Kambalda地区(WA)南部,Eyre半岛(SA)东南部和Cobar(NSW)北部地区的样品,显示了区域(放射性)不平衡,偏~(226)Ra。 在昆士兰东北部的两片石炭纪火山岩发育地带发现土壤富铀。活度比值的弥散分布表明,不平衡将对航空γ测量获得的铀道数据的噪声有影响。低计数率的统计噪声(反映土壤中的低铀含量)和铀镭不平衡的综合作用导致铀道数据产生40％～60％的变化。数据的这种变化通过合适的滤波可在某种程度上得到改善。
Measurements of uranium and radium in 445 soil samples taken from all over Australia showed that the average content of uranium in soil was 2.0 × 10 -6 and the activity ratio of U / ~ (226) Ra was 1.09. Although the range of single sample values varies widely, the overall uranium-enriched soil is more abundant than the radium enriched soil. Samples of the southern Cross-Kambalda region (WA), southeast of the Eyre Peninsula (SA) and northern Cobar (NSW) show a regional (radioactive) imbalance of ~ 226 Ra. Soil was enriched with uranium in two Carboniferous volcanic rocks in northeastern Queensland. The dispersion of activity ratios suggests that the imbalance will have an impact on the noise of uranium tract data obtained from aeronautical gamma measurements. The combined effects of low count rates of statistical noise (reflecting low levels of uranium in the soil) and uranium radium imbalance result in 40-60% variation in uranium data. This change in data can be somewhat improved by suitable filtering.