Measurements of 232Th/238U ratio using different techniques: A comparative study

Abstract

The present work was conducted to determine Th/U ratios in different types of natural rock samples (sedimentary, conglomerate, igneous and sediments) using high-purity germanium detector, solid state nuclear track detectors and inductively coupled plasma mass spectrometers. A thin source approach method for alpha tracks measurements was used. A new method was introduced for forming a thin layer of the rock sample. The track densities were obtained using an optical microscope coupled with a digital camera and spark counter. Even though the measurements were carried out using very different techniques, they showed comparable values of Th/U ratio for most of the rock samples.