208Pb/206Pb versus 207Pb/206Pb of Iwate glassy melt inclusions. The compositions are clustered between DMM and EMII mantle endmembers. The ellipses represent the two sigma errors on the measurements. The green squares are the Pb isotope compositions of the Iwate whole rock (Shibata and Nakamura, 1997: Hanyu et al., 2006). The triangles are the local reservoirs (gabbros in filled red, Sato, 1975; Japan Trench sediments in brownish color, Plank and Langmuir, 1998; average Pacific oceanic crust in blue, White et al., 1987). A mixture of these reservoirs can explain the variation in Pb-isotope compositions found in the melt inclusions.