Popis: |
The chemical and mineral composition of gabbroids of the pre-Jurassic basement of the Syunay-Salin area located in the Arctic part of the West Siberian megabasin on Yamal Peninsula is studied. Borehole 45 has drilled a layered gabbrodiorite intrusion, which was previously considered monotonic diorite one. The gabbroids are metamorphosed under conditions of the lower degree of the greenschist facies of metamorphism and also underwent propylitization, which is resulted in the formation of sulfdes including pyrite, chalcopyrite, also pyrrhotite, pentlandite, cubanite, samaniite and galena. According to mineral geothermometers, sulfde dissemination in Syunay-Salin gabbroids formed at temperature of ~200 °С. |