Granitoids of the Netpneyveem Tin-Tungsten-Gold Ore District, Western Chukotka

In this paper, we report new data on the age (U–Pb SIMS), petrogeochemical, isotopic composition, and geodynamic settings of Cretaceous granitoid complexes of the Netpneyveem ore district in Western Chukotka. The ages obtained for biotite granites of the Konevaam stock (114 ± 1 Ma) and leucogranites of the Elvenei massif (107 ± 1 Ma) are correlated with Aptian and Albian stages of intrusive magmatism associated with extension following collision between the Chukotka microplate and the Siberian (North Asian) continent. Sr–Nd isotopic composition of the studied granitoids indicates a significant contribution of mature continental crust to the magma source. This is supported by the Mesoproterozoic model ages of granitoids and the presence of Neoproterozoic inherited cores in zircons. Geochemical characteristics of rocks from the Konevaam stock are compared with those of the reduced intrusions likely associated with gold mineralization. Data on the age and composition of intrusive rocks of the Netpneyveem district elevate expectations for the identification of new ore objects within its boundaries and increase the prospectivity of this cluster.