La-Ce and Sm-Nd isotopic systematics of early Proterozoic leucogranite with tetrad REE pattern

We report La-Ce and Sm-Nd isotopic data for leucogranites having tetrad rare earth element (REE) patterns at Imweon area in the northeastern Yeongnam Massif, South Korea. The leucogranites are strongly peraluminous (A/CNK = 1.18-1.79) S-type granite generated by the partial melting of metasediments, which consist of quartz, K-feldspar, plagioclase, muscovite, biotite, garnet and sillimanite. The leucogranites have three types of chondrite-normalized REE patterns: one showing a tetrad REE pattern of M-type with a large negative Eu anomaly, another with slightly V-shaped REE pattern with a positive Eu anomaly, and third with an REE pattern of crustal type with an LREE-enriched and HREE-depleted pattern. U-Pb zircon ages and, Sm-Nd and Rb-Sr whole-rock ages from the leucogranites are 1853 +/- 15 Ma - 1859 +/- 14 Ma (2 sigma), 1833 +/- 220 Ma (2 sigma) with epsilon(Nd)(1.83 Ga) = -6.6 +/- 5.5 (2 sigma) and 1740 +/- 71 Ma (2 sigma) with initial Sr-87/Sr-86 = 0.755 +/- 0.050 (2 sigma), respectively. These values suggest that the leucogranites were emplaced from magma formed by partial melting of the crustal material. In the epsilon(Ce)-epsilon(Nd) diagram, the present Ce and Nd isotopic compositions of the leucogranites with a tetrad REE pattern are plotted in the positive epsilon(Nd) and epsilon(Ce) field whereas those of the leucogranites without tetrad REE pattern are in the negative epsilon(Nd) and positive epsilon(Ce) field. The initial Ce isotope values of the leucogranites with a tetrad REE pattern are plotted in a range of -2.31