| Abstract |
Yagodninskaya-Bannaya hydrothermal-magmatic system is a part of Banno-Karymshinkii long-existing (from the early Miocene to Holocene) centre of magmatic, geothermal and ore-forming activity. This centre is located within one of the most geodynamically complicated region of Kamchatka: South-Kamchatka depression of the infolded-block zone of East-Kamchatka volcanic belt, and is a large geothermal (ore) region. The region is characterized by propagation of contrasted composition rocks, wide occurrence of ignimbrites and rhyolite tuffs, formation of large calderas and dome-ring structures. Yagodninskaya-Bannaya hydrothermal-magmatic system is localized within the dome-ring volcanic-tectonic structure with a diameter of about 20 km. The central part of the structure is distinguished by accumulation of large multi-phase intrusive-subvolcanic and extrusive-subvolcanic complexes whose composition ranges from syenite-diorites to trachyliparite and basalts. Yagodninskoye deposit of zeolite materials, perlites and active minerals additives is confined to the extrusive-subvolcanic complex of elevation 1081: a more than 100 m thick stratum of vitro-lithoclastic tuffs contains clinoptilolite, mordenite and other high-silica zeolites up to 80-90% of rock volume. Rocks in the region are distinguished by elevated alkaline condition and hydrothermally-altered rocks are distinguished by high contents of potassium. Fields of propylites, secondary quartzite and argillaceous rock areas with diffused sulphide mineralization and quartz (quartz-carbonate) veins propagate on the periphery of the hydrothermal-magmatic system. The epithermal ore deposit and Bolshe-Bannoye geothermal deposit are confined to one of such large intrusive-subvolcanic complexes of syenite-diorites-dacites. Probably, another discharge of thermal waters named Maliye Banniye Springs is connected to this complex. Hydrocarbonate infiltration waters of Bolshe-Bannoye geothermal deposit are formed with participation of a deep-seated source, they contain elevated concentrations of numerous chemical elements (boron, fluorine, a number of metals) and have balneology properties. The region is a great tourist destination „Ÿ there have been recently built two spa-tourist compounds at the geothermal deposit, however the place can be reached only by off-road vehicles. On the whole, the described geothermal (ore) region and Yagodninskaya-Bannaya hydrothermal-magmatic system have large mineral and energy resources and are of a significant importance for future socio-economical development of Kamchatka Krai. A concept for such development can only be built upon compilation of results and new comprehensive scientific studies. Based on lithological, petrographic, mineragraphic, hydrogeochemical and other activities, the authors of the report suggested a working model for evolution of post-magmatic, hydrothermal-metasomatic and geothermal processes in the structure of the Yagodninskaya-Bannaya system. This work has been carried out with a financial support from the Russian Foundation for Fundamental Research (Project 13-05-00262) and Far-Eastern Division of the Russian Academy of Science. |