Measured values for the NBS 987 (Sr) and La Jolla (Nd) isotopic standards are 87Sr/86Sr =0.71026 and 143Nd/144Nd= 0.511859 with total measured ranges of +/-0.000026 and +/-0.000014, respectively. A 1 per mil/amu fractionation correction was applied to Pb isotoperatios, based on repeat measurements of NBS 981, to conform to the values of Todt et al. (1969). External uncertainties for 206Pb/204Pb and 207Pb/204Pb are less than +/- 0.01, and for 208Pb/204Pb are less than +/- 0.03. Total procedural blanks for Sr, Nd and Pb isotope measurements are 20, 5 and 50 pg, respectively. Parent-daughter elemental concentrations were obtained by quadrupole ICPMS, on the samespecially treated sample material used for isotope ratio analysis. Replicate analysis of rock standards indicates that Sr concentrations are precise to within 2.5%, Rb, Sm and Nd are precise to within 5% and U, Th and Pb are precise to within 8%. Initial (age-corrected) isotope ratios were calculated assuming the numerical sample ages. epsilonNd(t) values are calculated for age-corrected sample and CHUR Nd isotope ratios (143Nd/144NdCHUR(t = 0) = 0.512638, 147Sm/144NdCHUR = 0.1967).