Coastal seawater sample prep for Th isotopes

This method specifies the minimum requirements and laboratory methods for measuring ²²⁸Th, ²³⁰Th and ²³²Th in river water and coastal seawater with high thorium contents.

River- and sea-water samples are collected in acid-cleaned containers and pre-treated on board, by filtrating, acidifying and co-precipitating. Post processing is conducted in the land laboratory by purifying Th isotopes via anion-exchange column. Thorium isotopes are finally measured by alpha spectrometry.