234U/238U isotope ratios in groundwater from Southern Nevada: a comparison of alpha counting and magnetic sector ICP-MS

Uranium, radium and 40K isotopes in bottled mineral waters from Outer Carpathians, Poland

“…This result means that there is no radioactive equilibrium between the parent nuclide 238 U and its daughter 234 U in all these mineral waters. The state of radioactive disequilibrium in groundwater was already pointed out by other authors (see Cizdziel et al, 2005;Hakam et al, 2001 and references herein;Osmond et al, 1983). There are two different isotopes ( 234 Th and 234 Pa) present between the parent nuclide 238 U and its progeny 234 U in the radioactive decay series.…”

Uranium isotopes in groundwater from the continental intercalaire aquifer in Algerian Tunisian Sahara (Northern Africa)

“…The trend line is defined by two parameters: the y-intercept, which is the 234 U/ 238 U AR of the U being leached from the host rock, and the slope of the trend line, which is the 234 U-excess per kilogram (U-equivalent ppb) and is characteristic of the pre-leach water. 234 U-excess corresponds to the hypothetical concentration that the 234 U isotope has in excess to the 238 U concentration and has no real physical meaning as the actual mass of the 234 U isotope is w18 000 times less that the 238 U mass (Cizdziel et al, 2005). The unit for 234 U-excess is U-equivalent parts per billion, which is the concentration in micrograms per kilogram of an equilibrated amount of 238 U ( 234 U activity per mass of water) (Dabous and Osmond, 2001).…”

Geochemical Behavior of Uranium and Radon in Groundwater of Jurassic Granite Area, Icheon, Middle Korea

“…Since the uranium level is negatively constrained by DO and Eh, it can be inferred that high uranium was derived, not from swallow aquifer, but from moderate to deep aquifers, though it might be present as an insoluble species. Likewise, there is a decrease in the uranium level with increasing oxidizing condition [40]. Mostly uraniferous minerals in Jurassic granites occur as partial replacements in some accessory mineral phases such as monazite and apatite, or in rock-forming minerals such as feldspars and micas [41,42].…”