THE AGE OF GOLD MINERALIZATION OF THE UNGLICHIKAN DEPOSIT (Russian Far East): RESULTS OF 40Ar/39Ar DATING
A.Yu. Kadashnikova1, A.A. Sorokin1, A.V. Ponomarchuk2, A.V. Travin2, V.A. Ponomarchuk2
1Institute of Geology and Natural Management, Far Eastern Branch of the Russian Academy of Sciences, Blagoveshchensk, Russia
2V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Mongol-Okhotsk Orogenic Belt, Unglichikan gold deposit, gold, Ar/Ar geochronology
Abstract
The isotope-geochronological studies of ore metasomatites from the Unglichikan gold deposit have shown their age of 136-140 Ma. There are no data on magmatism of this age within the study area; therefore, it is impossible to associate the ore mineralization of the Unglichikan deposit with magmatic processes. The thermal event superposed on the host rocks of the Zlatoustovsk Formation beyond the ore zone is dated at 140 ± 2 Ma. Thus, the last stage of regional metamorphism and deformation and the formation of ore metasomatitesare are of the same age. We believe that the orogen deformation processes accompanied by hydrothermal activity played a significant role in the mobilization and redistribution of ore matter and in the formation of the Unglichikan deposit.
|
