GEOLOGICAL STRUCTURE and MINING DEVELOPMENT of the URALS Post-Conference Tour Perm – Yekaterinburg – Nizhny Tagil - Perm 19-22 July 2019
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GEOLOGICAL STRUCTURE AND MINING DEVELOPMENT OF THE URALS Post-conference tour Perm – Yekaterinburg – Nizhny Tagil - Perm 19-22 July 2019 Editors Liudmila S. Rybnikova, Oksana B. Naumova Yekaterinburg-Perm, 2019 Geological structure and mining development of the Urals. Post-conference tour. Perm–Yekaterinburg– Nizhny Tagil–Perm. 19-22 July 2019 / Liudmila S. Rybnikova, Oksana B. Naumova, Petr A. Rybnikov, Vladimir A. Naumov, Vera Yu. Navolokina, Vitaliy E. Sosnin, Igor S. Kopylov. 2019. – 32 p. ISBN Since 1979 the «International Mine Water Association» has been organizing annual international meetings focused on various aspects of mine water, including its hydrology, chemistry, biology, environmental aspects, and potential reuse, as well as how best to control it through better prediction, mine water management and treatment. The IMWA2019 Conference theme was «Mine water: technological and ecological challenges». The conference was held during 15-19 July, 2019 in Perm on the basis of Perm State University. The post- conference tour gives a unique opportunity to cross the Ural mountains twice and see the features of change in the geological situation in different structural- tectonic zones: from the East European platform, the depression area of the region (foredeep), Western Ural fold system (advanced folds of the Urals), the Central Urals mega anticlinorium (Central Ural uplift), the Main Ural fault and the Tagil synclinorium (deflection) of Tagil-Magnitogorsk mega synclinorium. The main stops along the route are the old Ural cities founded as places of development of mining and historical sites. These are the points of discovery of the first oil in the Volga-Ural oil and gas province, the first diamond, the first ore and placer gold, the oldest iron ore and copper deposits. The tour includes visit of Europe-Asia Border; Gold and Mine Museum (Berezovsky); Museum of geology at Ural State Mining University (Yekaterinburg); the Demidovs’ Leaning Tower (Nevyansk); Eco-industrial technology park «The Demidov’s Museum- plant» and The Main open-cut mine of Vysokogorsky ore mining and processing plant (Nizhny Tagil); a monument to the first diamond in Europe (Promysla village); a stele to oil discovery (Verkhnechusovskiye Gorodki). Post conference tour was jointly organized by the Institute of mining of Ural Brunch of Russian Academy of Science (Yekaterinburg) and Perm State University. Front cover: Ural "pyramids" - abandoned talc quarry "Old lens" (photo by Andrey Firsov) Back cover: The Russian Gold Rush. National Geographic in Russia (after https://vk.com/miningmuseum?z=video-77123354_456239027%2Fvideos- 77123354%2Fpl_-77123354_-2) 2 During the tour you will have a unique opportunity to cross the Ural mountains twice and see the features of change in the geological situation in different structural-tectonic zones: from the East European platform, the depression area of the region (foredeep), Western Ural fold system (advanced folds of the Urals), the Central Urals mega anticlinorium (Central Ural uplift), the Main Ural fault and the Tagil synclinorium (deflection) of Tagil-Magnitogorsk mega synclinorium (fig. 1). Figure 1. Geological map of the tour area The main stops along the route are the old Ural cities founded as places of development of mining and historical sites. These are the points of discovery of the first oil in the Volga-Ural oil and gas province, the first diamond, the first ore and placer gold, the oldest iron ore and copper deposits. The geological structure of the Urals The Urals is the border between two parts of the world — Europe and Asia. The border is drawn along the axial part of the mountains, and in the South-East along the Ural river. As far as the nature is concerned, the Urals is closer to Europe than Asia in this respect which is influenced by its clearly expressed asymmetry. The mountain belt of the Urals has affected the climate of the region which varies in three directions: from North to South, from West to East and from the foothills of the mountains to their tops. The North is 3 characterized by permafrost, the South – by fertile soil. The average temperature in winter in the North is -20oC, in summer +15oC, in the South it is -16oC in winter, and +20oC in summer. The "stone belt" of the Urals and the adjacent elevated plains of the Urals extend from the shores of the Arctic ocean in the North to the semi-desert regions of Kazakhstan in the South. For more than 2,500 km they divide the East European and West Siberian plains. The main part of this region is the Ural mountain system. The Ural mountains consist of low ridges and massifs, the highest of them are located in the Circumpolar (Narodnaya mountain — 1895 m), Northern (Telposiz mountain — 1617 m) and Southern (Yamantau mountain — 1640 m) Urals. The massifs of the Middle Urals are much lower, usually no higher than 600-650 m. The Western and Eastern foothills of the Urals and foothill plains are dissected by deep river valleys. In the Urals and near the Urals region there are many rivers and lakes, several hundred ponds and reservoirs were created. From the point of view of the geosynclinal approach, the Urals belongs to the number of ancient folded mountains (fig. 2). In the Paleozoic there was a geosyncline here; the seas rarely left its territory. They changed their boundaries and depth leaving behind a powerful thickness of precipitation. The Urals experienced several orogenic processes. Caledonian folding was manifested in the lower Paleozoic (including the Salair folding in the Cambrian). Although it covered a large area, it was not the main one for the Ural mountains. The main folding was Hercynian. In the East of the Urals it began in the middle Carboniferous, and during the Permian period it spread to the Western slopes. (Kopylov et al., 2015). The most intense Hercynian folding was in the East of the ridge. It was manifested here in the formation of strongly compressed, often overturned and recumbent folds, complicated by large thrusts, leading to the emergence of scaly structures. Folding in the East of the Urals was accompanied by deep splits and the introduction of powerful granite intrusions — up to 100-120 km long and 50-60 km wide. Much less energetic was the folding on the Western slope, it is dominated by simple folds, thrusts are rare, there are no intrusions. Tectonic pressure, which resulted in folding, was directed from East to West. The rigid foundation of the East European platform prevented the spread of folding in this direction. The most compressed folds are in the Ufa plateau where they are very complex even on the Western slope. After the Hercynian orogenesis, folded mountains appeared where there had been the Ural geosyncline, and later tectonic movements were in the form of block uplifts and descents which were accompanied by places, in a limited area, by intensive folding and fractures. In Triassic-Jura most of the Urals remained land, there was erosion processing of the mountainous terrain and its surface, mainly on the Eastern slope of the ridge. 4 Reference designations: 1 – schists, sandstones, limestones; 2 – granites, quartzites, gneisses, amphibolites, crystalline schist, eclogites; 3 – mudshales, argilliths, aleurolites; 4 – phyllites, siliceious schits, limestones, andesites, tonalities, diorites, basalts, dolerites, gabbro, pyroxenits, ophiolitic peridotites Figure 2. Schematic geological section of the Urals – contact of lithospheric plates: two borders "Europe-Asia". Done by I. I. Popov on the basis of A. A. Savelyev’s materials (Schematic …, 2018) 5 6 Figure 3. Tectonic scheme of the Middle and Northern Urals (VSEGEI, PSU) 7 Geological structures which we are going to cross during the tour from West to East are: the East European platform (sedimentary cover of the Russian plate), the Ural foredeep (depressional area), the Western Urals area of folding, the Central Ural uplift, Trans-Ural megazone (Tagil mega synclinorium) (fig. 3). Eastern European platform. In its structure there are two structural floors: the ancient crystalline basement of the Archean-lower Proterozoic age (Karelian, more than 1.6 billion years old) and subhorizontically lying on it sedimentary cover of upper Proterozoic, Paleozoic sediments (Russian plate). The sedimentary cover consists of little-modified sedimentary rocks of different ages – from the upper Proterozoic (Riphean, Vendian) to Cenozoic included. At the base of the platform cover there are terrigenous sediments of the Vendian- Cambria; higher in the section, subhorizontally lie carbonate and terrigenous- carbonate rocks of the middle and upper Devon, carbonate and terrigenous- carbonate rocks of Carboniferous, carbonate – lower Permian, terrigenous - middle and upper Permian, Triassic and Jurassic. Most of the territory is occupied by continental rocks of the upper and middle parts of the Permian system, discovered here by Roderick Impi Murchisson (1792–1871). Murchisson is a British geologist and traveler who first described and explored the Silurian, Devonian and Permian geological periods. Murchison made three trips to Russia. According to the research results, he justified for the first time the allocation of a new geological system – the Permian period. In the sedimentary cover, flat positive and negative rounded structures are developed: mega arches, arches, mega cavities and hollows, smaller domes, shafts and depressions, local uplifts. Ural Boundary Deflection (depression area) is a boundary linear structure between the platform and the folded area, both in geographical position and internal structure. The Ural Boundary Deflection is a large synclinal structure separating the Russian plate from the Ural Boundary Deflection Ural folded region. The boundary deflection is characterized by a deeper foundation than on the platform (up to 9 km or more). In the cut of the foredeep are allocated thick series of rocks of halogen (carbonate-sulphate-salt) formations of the Kungur layer of the Permian system and biogenic reefs of artinskaya tier of the Permian system. Mainly lower Permian sediments are exposed In the trough, partly overlain by middle Permian sediments.