Zircon from Intraplate Gabbroic Rocks of Western Chukotka (Anyui Plutonic Complex) and Interpretation of Its Age.

The timing of intraplate magmatism in Western Chukotka manifested in the formation of gabbroic rocks of the Anyui plutonic complex of the Anyui–Chukotka fold belt is proved by U–Th–Pb (SIMS) age of zircon. The results obtained and data published suggest that intensive intraplate magmatism in the Chukotka microcontinent was commenced at the time corresponding to the Permian–Triassic boundary and was terminated no later than in the Middle–Late Triassic. This intraplate magmatism was coeval with the breakup of Pangaea, and it probably took place at rifted continental margin settings. [ABSTRACT FROM AUTHOR]