| Abstract: | In this paper we provide data on the oldest island arc complex of Taimyr, which was established within the Central-Taimyr accretionary belt. We demonstrate its relationship with the mainly turbiditic back-arc basin complex. U-Pb isotopic data for zircons are presented from a plagiogranite and a plagiorhyodacite, indicating that the island arc formed 961–969 m.y. ago from a substance with a Mezoproterozoic model age: T Nd(DM) varies from 1170 to 1219 Ma. Paleomagnetic investigations performed on the island arc complex rocks showed that the paleomagnetic pole of the island arc is close to synchronous poles, obtained for the south-east of the Siberian craton. Consequently, the island arc whose relicts are preserved in the modern structure of the Three Sisters Lake region was located in close proximity to the Taimyr margin of Siberia at the moment of its formation and could be separated from the continent by a back-arc basin. The data obtained have a fundamental significance for geodynamic paleoreconstructions in the Arctic sector for the Neoproterozoic. |
