КРУПНООБЪЕМНЫЕ ЗОЛОТОРУДНЫЕ МЕСТОРОЖДЕНИЯ В УГЛЕРОДИСТЫХ ФОРМАЦИЯХ КАК ВОЗМОЖНАЯ ОСНОВА РАСШИРЕНИЯ СЫРЬЕВОЙ БАЗЫ ЗОЛОТА РОССИИ

Large-volume gold-ore deposits in carbonaceous formations as a practicable basis for expansion of the gold resource base of Russia

Large-volume deposits of disseminated gold in carbonaceous carbonate-clastic and clastic strata, deposits of the Carlin type, and carbonaceous gold-ore formations become the leading type of commercial gold deposits both in Russia and the world though the formation type has been distinguished as independent recently enough. The standard model of the deposit of this type calls for the obligatory presence of disseminated sulfide mineralization and organic matter, very fine-grained texture of ore minerals, high role of plicated tectonics In localization of gold ores, as well as the obligatory presence of thinly laminated carbonaceous silt carbonate rocks. In the mid 80s, American geologists investigated 40 gold-ore prospects in the Great Basin (USA) and delineated a group of disseminated gold deposits. According to the character of the hosting medium, the disseminated deposits are subdivided into volcanic-hosted and sedi-ment-hosted. The interest of the gold-mi-ning Industry to deposits of this type Is caused by many reasons, the most important of them are: the possibility of open mining; huge volumes of ore mass, which despite steadily reducing average gold contents enable to increase volumes of gold output in geometric progression through constant perfection of metal recovery technologies. In Russia, carbonaceous strata occupy spacious areas in the time interval from the Riphean to the Paleogene due to vast territories of the country, variety of geological structures and geodynamic settings of their formation. To date, tens of gold-ore deposits that may be conventionally assigned to the Carlin type are revealed, explored and successfully mined within them. According to data of TsNIGRI specialists, hypothetical resources of gold deposits of the gold-sulfide and quartz-gold commercial/geological types in clastic-carbonaceous and carbona-te-clastic complexes account for 28-30% of the total. When analyzing the evolutionary/age aspects of gold ore genesis in carbonaceous strata, it is worthy of note that 7 belts at least with maximal development of carbonaceous strata in which gold-ore deposits assigned to the Carlin type are discovered, mined or prepared for mining are delineated within folded areas of Russia; they are as follows (from west to east): Ural, Yenisei, S. Siberian, Verkhoy-ansk-Kolyma, Omolon-Chukotka, Sikho-te-Alin, and Koryak-Kamchatka. The belts correlate with major gold-mining regions of Russia rather well.