(Table 5) Rb-Sr and Sm-Nd isotopic systems in pillow lavas, their chilled glasses, and underlying holocrystalline rocks dredged from the Markov Deep, Sierra Leone Site, MAR 5-7°N

1) For 87Rb/86Sr error did not exceed +/-1% (2 sigma av.). 2) For 87Sr/86Sr error did not exceed +/-0.002% (2 sigma av.); based on replicate measurements of SRM-987 isotope standard (87Sr/86Sr = 0.710247+/-14). 3) For 147Sm/144Nd error did not exceed +/-0.2% (2 sigma av.); based on results of independent replicate measurements of BCR-1 standard and duplicate analyses of some samples. 4) For 143Nd/144Nd error was +/-0.0015% (2 sigma av.); based on replicate measurements of the Nd2O3 (143Nd/144Nd = 0.512407+/- 8) laboratory standard. 5) e-Nd values were calculated with respect to parameters of the uniform chondrite reservoir 143Nd/144Nd = 0.512638.