Uranium isotopes in groundwater from the Jeffara coastal aquifer (southeastern Tunisia)

The distributions of U-238 and U-234 in groundwater from the Jeffara aquifer were studied by using alpha spectrometric methods. The concentration ranges of 238U and U-234/U-238 activity ratios were 1.34 +/- 0.17 to 3.43 +/- 0.38 ppb, and 1.43 +/- 0.23 to 1.82 +/- 0.27 respectively. Variations in concentrations can be related not only to lithostratigraphic formations but also to different origins of groundwater. U content of Jeffara are found very similar to those of Continental Intercalaire aquifer in both El Hamma and Chenchou regions, indicating that the Continental Intercalaire is the dominant source of the groundwater. (C) 2010 Elsevier Ltd. All rights reserved.