Mapping 238U decay chain equilibrium state in thin sections of geo-materials by digital autoradiography and microprobe analysis

Appl Radiat Isot. 2018 Oct:140:228-237. doi: 10.1016/j.apradiso.2018.06.018. Epub 2018 Jun 25.

Abstract

A new approach is proposed in order to spatially localize and determine the equilibrium state of natural decay chains on hand-scale geological samples, thanks to a combination of three techniques: 1) Elementary chemical mapping by microprobe; 2) Alpha autoradiograph by gaseous detectors and 3) bulk alpha particle spectrometry. The quantitative nature of alpha autoradiograph and its comparison with U chemical maps allows to locate radioactive equilibrium state in four samples. This equilibrium state was confirmed by alpha spectrometry analysis.

Keywords: Alpha particle; Alpha spectrometry; Digital autoradiography; Radioactive equilibrium; Uranium.