Pyrite from Sulfidization Zones of Terrigenous Complexes in the Yana-Kolyma Orogenic Belt (North-East Russia): Generations, Typochemistry, Mineral Associations
Finely disseminated sulfide mineralization in terrigenous carbon-bearing strata is known to have a certain metal-bearing potential and to be an additional source of ores for deposits. In the zones of finely disseminated sulfide mineralization in the Debinsky, Chay-Yuryinsky and Orotukan-Srednekansky faults of the Yana-Kolyma orogenic belt, three generations of pyrite have been identified and studied: sedimentogenic, hydrothermal-metamorphogenic, and tentatively ore-hydrothermal with different sets of mineral associations. The studies were carried out in the Late Triassic and Early Jurassic sediments adjacent to the faults in the basins of the Spokoyny-Matrosova Creek, the Chay-Yurya River, the Ozyorny Creek, the Khara-Yuryakh Creek, the Nera River, and the Pravy Srednekan River. It was found that the sulfide mineralization had been formed in several stages. Morphological and genetic varieties of pyrite permit to distinguish sedimentary and metamorphogenic pyrite from ore pyrite. According to the quantitative analysis performed on a Camebax microanalyzer with an EDS detector X-Max Oxford, the main trace impurities in pyrite are As, Co, and Ni.