Assessment of sequential extraction and mineral separation for studying uranium-series isotopes in Regolith

In a weathering profile, the variation with depth of the uranium-series (U-series) isotopic composition can be modelled to estimate regolith production rates. Secondary phases precipitated from solution (solution-derived phases) and organic matter present in regolith may introduce uncertainties in the model and decrease the accuracy of regolith production rates. A pre-treatment to remove these phases could address this drawback. It is also necessary that the pre-treatment does not affect the isotopic composition of minerals derived from the bedrock (bedrock-derived phases). This thesis aims at developing the method to estimates regolith production rates using U-series isotopes. This was done by testing sequential extraction (a chemical procedure used to remove specific solution-derived phases and organic matter from regolith) and mineral separation as methods to isolate bedrock-derived phases. In addition, Useries,major elements and mineralogical analyses were used together to explore U-series isotopes fractionation during pedogenesis.