On the feasibility of determining the Th-230 activity in minerals without the addition of a Th radiotracer

摘要

The necessity of measuring the radioactivity of the Th-230 nuclide arises when attempting to solve a number of geochemical or geochronological problems based on the effects of radioactive disequilibrium in the U-238 series. It is the authors' opinion that the use of the traditional alpha- and beta-emitters of thorium as a radiotracer in order to determine the activity of Th-230 leads to various inconveniences and difficulties of a technical nature. The authors recommend using the Th-234 isotope contained in the study sample as the simplest and most natural way of measuring the chemical yield of the targeted nuclide (Th-230). A sequence of radio-analytical procedures is proposed that will provide a correct assessment of the radioactivity of Th-230. In addition, a specific example and an evaluation of the accuracy of the proposed methodology are presented, using actual experimental data.