Geological forecasting and prospecting for porphyry copper deposits and for their associated precious metal ores in the Kavral’yan metallogenic subzone of the Okhotsk-Chukotka minerogenic province

This paper describes the methodology and techniques of the forecasting and prospecting for porphyry copper deposits and associated precious metal ores, applied in the Kavral’yan subzone of the Penzhina-Anadyr metallogenic zone of the Okhotsk-Chukotka minerogenic province. These methods included: (1) development of a structural-formational, geophysical, and geochemical bases for the forecasting regionalization of the territory, with delineation of potential ore regions (equivalent to ore-magmatic systems with complex metallogeny) and of potential ore fields (corresponding to internal and flank portions of the regions); (2) development of forecasting exploration models of such ore-magmatic systems; and (3) identification, on this grounds, of promising areas for the geological exploration. Such an integrated approach has ensured a positive assessment of the prospects for revealing new porphyry copper deposits in the territory of southwestern Chukotka. This is evidenced by the established geological formations of three volcano-plutonic belts of different ages, potentially productive for porphyry copper and associated gold-polysulfide and gold-silver ores; identified ore-forming systems with metallogenic and ore-metasomatic zonality corresponding to the well-known models; and localized and approved forecasted resources of copper, gold, and silver in the Olkhovka ore field. These methodological approaches to solving the forecasting and exploration tasks can be implemented during the future exploration projects to discover new porphyry copper and their associated precious metal ore deposits in the Chukotka Autonomous Okrug and the Far Eastern Federal District as a whole.