| Реферат: | eng: New geological, petrochemical, mineralogical, and geochemical data are presented on the Uspensky granitoid massif in Southern Primorye. The massif consists of the rocks of two associations: (1) the early association (103. 3 ± 2. 4 Ma) consisting of garnet-bearing biotite and two-mica granite-leucogranites and (2) the late association (99 ± 2 Ma) represented by biotite (±amphibole) granodiorites, melanogranites, and granites. The granitoids of both associations have moderate potassic alkalinity and elevated alumina contents but differ in the proportions of alumina, calcium, and alkalis. The garnet-bearing granite-leucogranites are characterized by the highest Rb, Th, and U contents and the lowest Sr, Ba, Hf, and Zr contents. The REE distribution patterns have a quasi-symmetric shape and deep Eu minimums. The melanogranites show higher Sr and Ba contents and, as granites, are characterized by asymmetric REE spectrums with an insignificant negative Eu anomaly. The porphyraceous granodiorites and granites are peculiar in their lowered Sr and Ba contents, while the granodiorites have lowered contents of K, REE, Zr, Hf, Th, and U; elevated Nb contents; and a distinctive Eu minimum. In terms of their petrochemical and trace-element composition, the rocks of both the associations correspond to S-type granitoids formed by partial melting of compositionally close crustal protoliths. Thus, the formation of the Central Sikhote Alin plutonic belt in the setting of a transform continental margin was accompanied by the generation of S-granites at the early (Aptian) and late (Late Albian) stages. At the last stage, they formed simultaneously with calc-alkaline and subalkaline granitoids. © 2011 Pleiades Publishing, Ltd.
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