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Oleg Fedorenko , Scientific Institute of Natural Resources YUGGEO (Kazakhstan)
Bulat Uzhkenov, Committee of geology and subsoil usage of the Republic of Kazakhstan (Kazakhstan)
Mikhail Rafailovich, Scientific Institute of Natural Resources YUGGEO (Kazakhstan)
Aleksander Smirnov, Scientific Institute of Natural Resources YUGGEO (Kazakhstan)
Victor Krasnoborodkin, Scientific Institute of Natural Resources YUGGEO (Kazakhstan)
Igor Golovanov , Scientific-Research Institute of Mineral Resources (Uzbekistan)
Rena Maksumova, Institute of Geology, National Academy of Sciences (Kyrgyzstan)
Valentin Nikonorov, Kyrgyz methodical expedition of geological-economic researches, (Kyrgyzstan)
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The new Atlas of the CEA maps with expressed forecasting-minerogenic accent gives basis for serious practical usage. Substantiation of high potential of sutures zones (SZ) and intraplate shear zones on various kinds of mineral raw material, allocation of minerogenic regions as new element of the mineral deposits forecasting were established. SZs are widespread, but poorly investigated tectonic and metallogenic element of the folded belts. They are zones of collision of continents and microcontinents as a result of continental crust subduction. These zones composed by megamelange formed on place of convergent and transform boundaries of lithospheric plates. They contain bodies of ophiolites, metamorphic rocks of ultrahigh pressure, flysches, olistostromes, island arc volcanic strata, reef limestones, i.e. rocks of various geodynamic environments. Terrigenous detrital material and dynamic schists are the matrix of megamelange.
Minerogeny of SZ is extremely various. There are deposits of different ores: chromites, nickel-cobalt, copper-zinc-pyrites, platinum, mercury and antimony-mercury, industrial diamonds, gold, tantalum-niobium and tin. Composite origin of the SZs determines specificity of the imposed hydrothermal magmatic processes connected with subduction and collision, minerogenic specialization of mineral deposits. Oceanic environment leaves traces in form of ophiolitic allochthons. They are fragments of oceanic crust. The allochthons bear magmatic and hydrothermal mineralization (chromites, cobalt-nickel, copper-zinc-pyrites ores). Active margins involved in collision, promote formation of gold, polymetallic, copper-porphyry deposits. Environments of passive margins and aulacogens in collision zones are favorable for concentration of iron-manganese and lead-zinc ores. Collision granitoids are specialized on rare metals. Attachment of oil-and-gas basins to the sedimentary strata overlapping disappeared suture zones deserves steadfast attention.
More than 20 ore controlling SZs with original specialization of mineral deposit, including large and very large deposits are known in territory of CEA. They are distinctly traced on Mineral deposits map of CEA of 1:2 500 000 scale and Minerogenic maps of transboundary folded belts of 1:1 000 000 scale. This fact can serve at ore fields forecasting.
We consider as the main recommendation of the present report the program of scientific-research and geological exploration works «Geology, tectonics and prognostic evaluation of suture and shear zones of Eurasia». The Geological Services and leading geologists of Kazakhstan, Russia, Uzbekistan, Kyrgyzstan, China, Tajikistan, Turkmenistan, Azerbaijan, Georgia, Armenia and other countries participate or express readiness to participate in works of this program.
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