U-pb Isotopic Age, Composition, And Sourcesof The Plagiogranites Of The Kalba Range,rneastern Kazakhstan

摘要

Of special importance in the evolution of the Pale-oasian ocean is the Carboniferous-Permian stage, which reflects the closure of the oceanic basin and formation of the structure of the Central Asian fold belt (CAFB) in its present-day form [1]. This is also the time (320-280 Ma) when the largest Angara-Vitim granitoid batholith and conjugate synplutonic basite dikes in Transbaikalia, granitoid intrusions and bimo-dal basalt-rhyolite series of the Gobi-Tien Shan zone of South Mongolia, and the Kalba-Narym and Zharma-Saur batholithic bodies and preceding subalkaline gab-broids, picritoids, high-Al plagiogranitoids, and paleo-volcanic structures of the central type in Eastern Kazakhstan were formed. Unlike the Permian-Triassic stage, which was proved to be related to the Siberian superplume , the geodynamic nature of the Carboniferous-Permian magmatism of the CAFB remains controversial.