Nd isotopes were analyzed as oxides, and the isotopic fractionation correction applied was NdO/ NdO = 0.242436 (Nd/ Nd = 0.241572). The fractionation correction used for Sr was Sr/ Sr = 0.1194. Nd isotopic data are reported relative to the measured Nd/Nd values for the La Jolla Nd standard of 0.511855 ± 0.000012 total range. Sr isotopic data are reported relative to a Sr/Sr value of 0.71022 for NBS 987; the measured Sr/Sr for NBS 987 during the tenure of this study was 0.71021 ± 0.00002 total range. Total procedural blanks are less than 20 pg for Nd and Sm, less than 10 pg Rb, and less than 200 pg for Sr; all blanks are negligible for these analyses. 2SE = two standard errors; for Sr and Nd isotopes the errors are reported relative to the last digit(s).