Turan Lowland(redirected from Turan Depression)
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(also Turan Plain), a plains region in Middle Asia and southern Kazakhstan, consisting largely of deserts, including the Karakum and Kyzylkum. It is bounded by the Ko-petdag and the Paropamisus foothills in the south, the Caspian Sea in the west, the southern spurs and eastern foot of the Mugo-dzhar Mountains in the northwest, the Turgai Plateau in the north, the Kazakh Melkosopochnik in the northeast, and the Tien-Shan and Pamir-Alai mountains in the southeast. In the east, the lowland is separated from the Balkhash-Alakol’ Basin by the Chu-Ili Mountains and the elevated eastern edge of the Betpak-Dala Desert.
Most of the Turan Lowland corresponds to the Turan Plate, the folded foundation of which is covered with Mesozoic and Cenozoic deposits and is exposed in only a few areas, namely, the Karatau Mountains on the Mangyshlak Peninsula, the uplands of Kyzyl-Kiia and Sultanuizdag, and the hills in the central part of the Kyzylkum. Deposits of oil and gas are located on the Mangyshlak Peninsula.
The relief of the Turan Lowland is characterized by the alternation of accumulative lowlands and plains with relatively weakly dissected table plateaus: Ustiurt, Krasnovodsk, and the Zaunguz Karakum. Some parts of the lowland are below sea level (Kara-gie, 132 m below sea level). The highest elevations (more than 300 m) are found in the inselbergs located in the central part of the Kyzylkum-Tamdytau Desert (up to 922 m) and on the Mangyshlak Upland (up to 556 m).
Most of the Turan Lowland has a sharply continental, desert climate; the southern part has a subtropical climate. The soils are gray-brown and low in carbon in the north and carbonaceous in the south. In the southern foothill plains the soils are light and ordinary sierozems. Wormwood-saltwort, psammophytic, and ephemeral desert vegetation predominates. Clayey deserts with wormwood or wormwood and saltwort are widespread in the northern half of the Turan Lowland, as well as sandy and stony deserts; occasional solonchaks and takyrs are encountered. The southern half is characterized by subtropical deserts: loess and clay (ephemeral), sandy, and stony deserts, takyrs, and areas of solonchak desert. There are seasonal pasturelands in the Karakum, Kyzylkum, and other deserts. Agriculture is irrigated.
REFERENCESredniaia Aziia. Moscow, 1968.
N. A. GVOZDETSKII