The boundary between Europe and Asia is typically taken to be the Ural Mountains, a particularly straight mountain range that stretches 1,500 miles (2,400 km) from the Arctic tundra to the deserts north of the Caspian Sea. Naroda (6,212 feet; 1,894 m) and Telpos-Iz (meaning "nest of winds," 5,304 feet; 1,617 m) are the highest peaks, found in the barren rocky and tundra-covered northern parts of the range. Southern parts of the mountain range rise to 5,377 feet (1,639 m) at Yaman-Tau, in the Mugodzhar Hills. The southern parts of the range are densely forested, whereas the northern parts are barren and covered by tundra or bare rock.
The ural River flows out of the southern urals into the Caspian Sea, and the western side of the range is drained by the Kama and Belaya Rivers, tributaries that also feed into the Caspian Sea, providing more than 75 percent of the water that flows into this shallow, closed basin. The eastern side of the range is drained by the ob-Irtysh drainage system that flows into the Ob Gulf on the Kara Sea.
The urals are extremely rich in mineral resources, including iron ore in the south and large deposits of coal, copper, manganese, gold, aluminum, and potash. Ophiolitic rocks in the south are also rich in chromite and platinum, plus deposits of bauxite, zinc, lead, silver, and tungsten are mined. Basins on the western side of the urals produce large amounts of oil, and regions to the south in the Caspian are yielding many new discoveries. The urals are also very rich in rare minerals and gems, yielding many excellent samples of emeralds, beryl, and topaz.
The urals form part of the ural-Okhotsk mobile belt, a Late Proterozoic to Mesozoic orogen that bordered the Paleoasian Ocean. The ural Mountains section of this orogen saw a history that began with Early Paleozoic, probably Cambrian rifting of Baikalian basement, and Late Ordovician spreading to form a back-arc or oceanic basin that was active until the mid-Carboniferous. Oceanic arcs grew in this basin, but by the Middle Devonian began colliding with the East European continent, forming flysch basins. The Kazakhstan microcontinent collided with the Laurussian continent in the Permian, forming a series of foredeep basins on the Russian and Pechora platforms. These foredeeps are filled with molasse and economically important Middle to Late Permian coal deposits as well as potassium salts.
The urals show a tectonic zonation from the Permian flysch basins on the East European craton to the Permian molasse basins on the western slopes of the urals, then into belts of allochthonous carbonate platform rocks derived from the East European craton and thrust to the west over the Permian fore-deeps. These rocks are all involved in westward-vergent fold-thrust belt structures, including duplex structures, indicating westward tectonic transport in the Permian. The axial zone of the urals includes a chain of anticlinoria bringing up Riphean rocks, whose eastern contact is known as the Main uralian fault. This major fault zone brings oceanic and island arc rocks in large nappe and klippe structures, placing them over the passive margin sequence.
The eastern slope of the urals consists of a number of Ordovician to Carboniferous oceanic and island arc synformal nappes, imbricated with slices of the Precambrian crystalline basement. It is uncertain if these Precambrian gneisses are part of the East European craton, part of the accreted Kazakhstan microcontinent, or an exotic terrane. The eastern slopes of the urals are intruded by many Devonian-Permian granites.
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