This project will analyze the Hf and Nd isotopic, and trace element characteristics of different types of mantle materials and has three main goals: 1) to determine the Hf-Nd-isotopic compositions of peridotites. Abyssal peridotites and peridotitic material from ocean islands and continents will be studied to constrain the relationship between peridotites and mantle melts. Furthermore, this study will attempt to constrain the ages of the Hf-depletions which are a common occurrence in peridotites, and it will test whether Hf and Nd isotopes are correlated in peridotite materials. 2) to evaluate the use of the combined Hf-Nd isotope systems as indicators for degree and depth of melting of mid-ocean ridge basalts as proposed by Salters and Hart (1989). These melt parameters will be calibrated against those proposed by Klein and Langmuir (1987; 1989). 3) to determine the extent of the MORB and OIB field on a Hf-Nd isotope correlation diagram, with the goal of constraining the mixing relationships between MORB and OIB.
