Alkaline Мagmatism of the Southern Siberian Craton: Stages of Formation and Mantle Sources (A Review)
摘要
A review of geochronological, geochemical, and isotopic data on the alkaline complexes and massifs of different ages (1.91–1.88 Ga, 660–630, 400–370, 310–290, 250–240 and 150–113 Ma) of the southern margin of the Siberian Craton is presented. The geochemical and isotopic characteristics of Paleoproterozoic, Late Paleozoic, and Mesozoic alkaline complexes indicate the formation of rocks from a metasomatized lithospheric mantle, which was reworked in the Late Archean–Early Proterozoic during the formation of the continental lithosphere of the Siberian Craton. The isotopic and geochemical features of the above-mentioned alkaline rocks characterize slightly different geochemical enviroment of the processes that led to the formation of the ancient lithosphere of the Siberian Craton. Isotopic characteristics of the Neoproterozoic and Triassic alkaline complexes reveal a dominant contribution of the asthenospheric component. Their magmatism was controlled by tectonic processes related to the Rodinia supercontinent breakup, which provided an influx of asthenosphere, and by plume process.