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Based on isptopic age of Sm-Nd and its initial composition and its evolution obtained during the recent years of archean metamorphic magnesio-ferro the vocanics of upper mantle of the North China platform, it is concluded that the isotopic composition of Archean upper mantle of the North China platform is not homogeneous, and values of /Nd don not change regularly through the whole Archean; in contrast, they present obvious differences in different regions. All this demands that the unhomogeneity of Archean upper mantle of the North China platform inherits initial unhomogeneity of origin, and the origin of the North China platform should contribute to uneven accumulation of planetesimals.
Based on isptopic age of Sm-Nd and its initial composition and its evolution obtained during the recent years of archean metamorphic magnesio-ferro the vocanics of upper mantle of the North China platform, it is concluded that the isotopic composition of Archean upper mantle of the North China platform is not homogeneous, and values of / Nd don not change regularly through the whole Archean; in contrast, they present obvious differences in different regions. All this demands that the unhomogeneity of Archean upper mantle of the North China platform inherits initial unhomogeneity of origin, and the origin of the North China platform should contribute to uneven accumulation of planetesimals.