R.S. Harmon A. A. Levinson C.J. Bland R.S. Lively 1979 <div class="u-margin-s-bottom">Uranium-series disequilibrium studies carried out on samples from the Yeelirrie uranium deposit, Western Australia, indicate that uranium and radium have been migrating within the deposit during recent times, and are actually being removed from the deposit. Samples collected for<span>&nbsp;</span>²³⁰Th/²³⁴U age dating were found to be substantially out of equilibrium, with<span>&nbsp;</span>²³⁰Th/²³⁴U activity ratios ranging from 0.750 to 1.345. This can be explained by a dynamic hydrologic system in which there has been, and continues to be, uranium migration caused by leaching in this arid, oxidizing environment, and a fluctuating water table.</div><div class="u-margin-s-bottom">Recent, extensive<span>&nbsp;</span>²²⁶Ra migration (²²⁶Ra/²³⁰Th activity ratios range from 0.53 to 1.30), and a very low emanation factor (<i>E</i>) of<span>&nbsp;</span>²²²Rn limit the quantitative application of radon exploration techniques in this environment.</div> application/pdf 10.1016/0375-6742(79)90063-3 en Elsevier Disequilibrium in the 238uranium series in samples from Yeelirrie, Western Australia article