Geochemical and Cosmochemical Applications of Nd Isotope Analysis

Abstract

High-precision solid-sources mass spectrometry has been employed to identify variations in the isotopic composition of natural Nd. Alpha decay of the long-lived isotope Sm-147 to Nd-143 is the chief cause of natural variations in Nd isotopic composition. Results of the alpha decay provide a cosmochronological and geochronological dating tool which has advantages over Rb-Sr and U-Pb dating in the study of fractionated materials. Nd isotopic composition also provides an indicator of provenance for rare earths in terrestrial materials and may thus be used in petrogenetic investigations.