Determination of Uranium and Thorium Isotope Ratios by Inductively Coupled Plasma Mass Spectrometry

Measurement conditions were selected and a procedure was proposed for determining the ²³⁴U/²³⁸U and ²³⁰Th/²³²Th isotope ratios using an ELEMENT single-channel double-focusing inductively coupled plasma mass spectrometer. The procedure was tested in analyzing bottom sediments from Lake Baikal with the extraction preconcentration of uranium and thorium. The accuracy of the procedure was verified using certified reference materials and a model solution by comparing the results obtained with the data of spectrometry.