On the genesis of the gold-silver deposit Kupol (North-East of Russia)

A new version of genesis of the epithermal gold-silver deposit Kupol (Chukotka), its mineral composition of ores and conditions of ore-localization based on the analysis of published geological materials on the geological structure had purposed in this article. The active thermal ore-forming role of completing the volcanic cycle of the multiphase subvolcanic complex’ the proximal bodies of the Upper Cretaceous rhyolites had been proved. The main factors of this deposit’ formation and the conditions that favored the appearance of large ore bodies and rich ores were considered. The magma chamber, unified faulty magmatic and fluid conductor, rock screen, flank clusters of subvolcanic rhyolite bodies and their integral thermal anomalies that initiated and sustained the deep fluid thermal convection under the screen, its mixing with fractured pore and meteoric waters and formation of gradient temperature zones, were considered among the main factors. The conjugation of these factors in space and time, the active tectonic regime and the long-term preservation of the deformation plan were the favorable conditions for ore formation. They maintained the high permeability of the fluid conductor, prevented a wide dispersion of fluids and provided a telescopic deposition of different mineral parageneses.

On the genesis of the gold-silver deposit Kupol (North-East of Russia)

A new version of genesis of the epithermal gold-silver deposit Kupol (Chukotka), its mineral composition of ores and conditions of ore-localization based on the analysis of published geological materials on the geological structure had purposed in this article. The active thermal ore-forming role of completing the volcanic cycle of the multiphase subvolcanic complex’ the proximal bodies of the Upper Cretaceous rhyolites had been proved. The main factors of this deposit’ formation and the conditions that favored the appearance of large ore bodies and rich ores were considered. The magma chamber, unified faulty magmatic and fluid conductor, rock screen, flank clusters of subvolcanic rhyolite bodies and their integral thermal anomalies that initiated and sustained the deep fluid thermal convection under the screen, its mixing with fractured pore and meteoric waters and formation of gradient temperature zones, were considered among the main factors. The conjugation of these factors in space and time, the active tectonic regime and the long-term preservation of the deformation plan were the favorable conditions for ore formation. They maintained the high permeability of the fluid conductor, prevented a wide dispersion of fluids and provided a telescopic deposition of different mineral parageneses.

Selenga ore district in Western Transbaikalia: structural and mineragenetic zoning, genetic types of deposits and geodynamic settings of ore localization

Based on complex structural, geological, and mineragenetic metallogenic studies, taking into account the results of earlier subject-specific, prospecting, mapping, and exploration works, it has been established that Upper Paleozoic and Early Mesozoic tectono-magmatic structures are widely developed within the ore district. They are associated with the development of the transregional Upper Paleozoic Selenga-Vitim volcano-plutonic belt of riftogenic type as well as with the formation of the Early Mesozoic Western Transbaikalian zone of intraplate magmatism. The main commercially important mineral raw material resources of the Selenga ore district which are located in the ore clusters (the Kunaley, Kizhinga, Cheremshanka-Oshurkovo, Tashir etal.) and beyond their bounds are associated with the Late Paleozoic-Mesozoic magmatic activity. It is shown that molybdenum and beryllium are the main ore mineral resources within the investigated ore district which establish its mineragenetic features. The new material characteristics of the Upper Paleozoic and Early Mesozoic intraplate magmatic complexes and the associated deposits of mineral raw materials (Mo, Be, Ti, quartz, fluorite and apatite raw materials) and other promising ore objects of gold, uranium and rare-earth-barium-strontium mineralization are obtained. The geodynamic conditions of their formation and the main age boundaries of the ore-forming processes are revealed, the prospects of mining in the Selenga ore district and the involvement of this ore potential in the program of the regions economic modernization are estimated.