New Data on the Age of Magmatic Events in Oloy Tectonic Zone, West Chukotka Area (Evidences from Zircon U–Pb Dating)

Resumo

The following U–Pb ages (Ma) were obtained for zircons from volcanic rocks and granitoids representing various complexes of the Nembonda Depression (the Anadyr segment of the Okhotsk–Chukotka Belt): 147.7 ± 2; 123.8 ± 1.7; 119.3 ± 1.7; 95.8 ± 0.5; and 80.55 ± 0.96. These results support the hypothesis of a significant Aptian igneous event in the Verkhoyansk–Chukotka region and provide the basis for the revision the boundaries of the Okhotsk–Chukotka Belt.