234U and 230Th determination by FIA-ICP-MS and application to uranium-series disequilibrium in marine samples

J Environ Radioact. 2006;88(2):109-17. doi: 10.1016/j.jenvrad.2005.12.012. Epub 2006 Mar 20.

Abstract

A 234U and 230Th determination method based on an extraction chromatographic separation on a flow injection system coupled to a quadruple ICP-MS was developed. Two-milliliter UTEVA (Eichrom Co.) cartridges were applied as separation tool and 236U and 229Th as spikes. Loading and washing steps were carried out in 3 M HNO3 solution and 0.05 M ammonium oxalate applied to elute both uranium and thorium. The method was applied initially to the IAEA-327 soil reference sample and NIST SRM 4357 ocean sediment reference material, with the obtained 234U and 230Th concentrations in agreement with the reference levels. Samples from a deep-sea sediment core (2450 m water depth) were analyzed and based on 230Th/234U dating, a mean sedimentation rate of 3.3 cm ky(-1) was calculated. Samples from two sediment layers were also dated by 14C-AMS and the observed ages agree with the 230Th/234U results.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Geologic Sediments / chemistry*
  • Reference Standards
  • Seawater / chemistry*
  • Thorium / analysis*
  • Uranium / analysis*
  • Water Pollutants, Radioactive / analysis*

Substances

  • Water Pollutants, Radioactive
  • Uranium
  • Thorium