Gold-Porphyric Mineralization of the Kara Ore Knot in Eastern Transbaikal as a New Type of Auriferous Mineralization in East Siberia

摘要

On the basis of new data, the authors substantiate the occurrence of gold-porphyric large-volume mineralization, atypical for Transbaikal, within the Sretensk-Kara ore region situated in the zone of the Mongol-Okhotsk suture separating the area of proterozoids of the Stanovoi zone from early mesozoids of Southeastern Transbaikal. The auriferous mineralization is presented by three spatially superposed exploitation-genetic types: (1) veined; (2) mineralized zones; and (3) dispersed and streaky-impregnated (stockwork). All these types and the whole set of granodiorite-dioritic stock with dispersed and streaky-impregnated mineralization, zones of kali-sparization and sulfidization (in fact, by stockwork), and the dykes of quartz dioritic por-phyrites were formed as a result of the occurrence of a unified ore-magmatic system and constitute a large-volume deposit corresponding, by all the features, to the gold-porphyric type.