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Rosalia Djencuraeva, Institute of Geology (Kyrgyzstan)
Ilghiz Aitmatov, Institute of Physics and Mechanics of Rocks (Kyrgyzstan)
Oktiabrin Sadyrov, Alex Stewart Assay and Environmental Laboratories (Kyrgyzstan)
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The metallogenic history is closely connected with its geodynamic evolution that is an important controlling factor of ore systems development. A variety of geodynamic conditions characterize mineral deposits formation in Tien Shan. Interpretation of a number of metallogeny zones allows determining geodynamic complexes corresponding to continental and oceanic rifts, passive and active continental margins, island arc systems, and collision zones.
Continental rifting started at the R-V time. It is characterized by graben deposits, alkaline bimodal volcanic series, and magnetite-hematite shales (the Djetym large iron basin). Additionally to iron ore, the sequence contains vanadium-bearing horizons.
Disseminated gold-tellurium-tungsten-pyrite mineralization (that is the source of Kumtor deposit large polygenic formation) is associated with Vendian rift facieses that comprised of tilloid-carbonaceous-slate, argillaceous-siliceous, and carbonaceous deposits.
Island arcs formed in the Cambrian and Middle Ordovician. The Middle Ordovician subduction was completed with a collision and obduction of island arcs on the Northern Tien Shan continent. The collision entailed emplacement of granodiorite, monzodiorite, diorite intrusions and forming numerous porphyry gold-copper deposits. There are latitudinal zones in Kyrgyz range.
Within the Devonian marginal continental magmatic arc, porphyry gold-copper deposits are controlled by thrust-fault zones and related to monzonites (the Taldybulak Levoberezhny deposit).
The Beltau-Kurama volcanic-plutonic belt started evolving during the Middle Carboniferous. The Turkestan paleooceanic crust subducted beneath the Kyrgyz-Kazakh continent southern margin. In the volcanic belt, porphyry copper, molybdenum-copper, gold-copper, skarn base-metal deposits are known (Almalyk, Gava, Bozimchak).
At the same time, the backarc magmatic belt of the Middle Tien Shan appeared behind the Beltau-Kurama zone. It is characterized by gold-tungsten-telluride-pyrite, gold-scheelite-skarn deposits. It is in this belt, where the large gold deposit Kumtor is located.
The Late Carboniferous and Early Permian were characterized by a continent - continent collision. Complex gold mineralization formed at the contact with Permian leucogranite (Makmal).
The end of Tien Shan Paleozoic history was completed with intraplate processes related to the Paleotethys closure. For this stage, the widespread rifting was typical. The narrow grabens system was filled by subalkali basalt and andesite. Antimony-mercury (Khaidarkan, Kadamjai) and gold-antimony (Tereksay, Ishtamberdy) mineralization are known as deposits of jasperoid type. Gold-sulphide-quartz mineralization is located in rapakivi granites (Jangart, Togolok). Tin mineralization is hosted in hastingsite leucogranite greisens. The REE-Nb-Ta-Th mineralization is associated with leucogranite (Aktiuz) and carbonatite (Sarysai).
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