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Геология и минерально-сырьевые ресурсы Сибири-Geology and mineral resources of Siberia Ордовик Сибирской платформы Новая схема относится к четвертому поколению региональных стратиграфических схем палеозоя Сибирской платформы, планомерная разработка которых была начата в 1950 г. в рамках крупномасштабной государственной программы регионального геологического изучения всей территории СССР, и в первую очередь слабо изученных регионов Сибири. На базе Всесоюзного геологического института (ВСЕГЕИ) и Якутского геологического управления была создана комплексная Восточно-Сибирская экспедиция, которая проводила геологическую съемку м-ба 1:200 000 в сопровождении тематических работ по палеонтологическому обоснованию стратиграфической основы легенд этих карт. В ка

Facies zonation of the Paleozoic basement of West Siberian geosyncline and its surroundings is presented. Facies megazones are distinguished according to types of sedimentation. Analysis of lateral and successive sedimentary sequences shows that the available data are insufficient to map the facies distribution over the whole territory of the geosyncline for short time slices. Only the Late Devonian section is supported by data sufficient for the proposed facies zonation. Five megazones, I, II, III, IV, and V, are distinguished in the westward direction. First three megazones make up a single lateral facies succession and represent sedimentary environments on and around the Siberian continent. Megazone IV includes shallow-water volcanic and sedimentary rocks that compose the Kazakhstan continent bounded by Early and Middle Carboniferous sutures in the west and east. Megazone V comprises fold-thrust (island arc) complexes of the eastern Urals. The main events in the geologic history of the region were associated with the interaction of two major crustal masses (Siberian and East European continents) and the young Kazakhstan continent in the oceanic space called the Paleoasian ocean. Only few fragments of this space occur in the present-day framework of the territory, the greatest part being sunk in subduction zones, especially in the large zone of the Main Uralian Fault. Production and accumulation of organic matter in pre-Mesozoic deposits occurred on continental shelves, which are most promising for Precambrian and Paleozoic oil and gas.