Ustyurt Plateau
The Ustyurt plateau or Ust- Urt Plateau is a vast, desert- steppe to plateau in Central Asia. It belongs to the lowlands of Turan and Caspian Sea lies between the Aral Sea and the Western Valley on the territory of Uzbekistan, Turkmenistan and Kazakhstan. The plateau is about 180,000 square kilometers and stands out with a 60 to 150 m high escarpment from its surroundings. Its altitude is on average 160 to 200 m, the highest elevation is 370 m. The name Ust- Urt means by M. Goeje (1875 ) "Highland ".
Geologically it is a table-land of a large marl and limestone slab, in their sinks to salt lakes have formed. Below the plateau occur oil and gas. After surface configuration and vegetation four areas can be distinguished:
- Wide, completely flat Lehmregionen
- The great salt region of the Aral Sea
- Some hilly sand areas in the southeast
- The marl region in the east.
Pflanzengeografisch and geologically consists relationship to the southern foothills of the Ural Mountains, which continue as a ridge of Mugodscharen about 500 km to the northwest of the Northern Aral Sea.
The far- projecting into the Caspian Sea to the west peninsula Mangyshlak is usually counted for Ust- Urt, however, extending transversely to mountain axes. On the northern edge of the plateau they ( Gora Bessoki ) achieved in Mangistau Mountains an altitude of 556 meters.
On rivers of Ust -Urt is very poor. In the northwest of Tschegan flows, but gets lost in the desert soon. The only river Arass - Kuil on the east side turns west, in summer it dries up but for the most part.
Geology
Alexander von Humboldt led by 1830 first geological research. He put geognostisch and orographic a link to the Urals fixed, including in the almost parallel alignment of the Centralaxen. However Geologically, the Ust- Urt younger (see below) and mostly built up of horizontal tertiary strata.
The northwestern edge of the plateau shows an uninterrupted series of deep cuts whose terraces are often covered by large rubble of a shell - conglomerate. It has therefore been interpreted over 100 years ago as traces of a former Coast.
Today's geology sees a connection with the Sarmatian sea that stretched after the Oligocene from the Mediterranean via the Black and Caspian Sea to the Central Asian valley. To fluvial sediments from the adjacent mountains deposed on its banks, which were folded about the same time as the Alps. The Sarmatian sediments of the former sea consist of clay minerals, sand, sandstone, conglomerates and lime. Later crustal movements displaced the sea in a small part of southern Turan, while the North was raised.
In the Pliocene ( 3-6 million years ago ) the sea came back again, but no longer reached its former proportions and created the border between the Ust -Urt plateau and the Kara Kum desert and the Ungus ( an outflow loose Valley, surrounded by the desert). The tectonic movements produced in addition to many small valleys and the Aral basin, which corresponds to a portion of the sunken base.
With the exception of the slightly raised central part, the plateau is built up quite uniform and consists of horizontally lying marls and limestones of the middle and upper Sarmats, including lying red sands and clays, sands and conglomerates under these ferruginous of Aquitans. In the southern part of the erosion edge of the panel from Karabugas golf runs to the southeast to the Karakum Desert and makes this pad visible, as some troughs and tubes on the plateau itself
At its northern edge and the base of the Miocene is open: every layer sequences of Oligocene, Eocene and Paleocene are present in larger edge distance and the Upper Cretaceous. You are almost horizontal - low slope to the south - and are unfolded, which emphasizes the Ust- Urt as a separate block. Only between Oligocene and Miocene unconformity shows a weak to tectonic movements of this period.
Animal and plant life
The desert-like Ustyurt Plateau is home to diverse - some rare - species such as the saiga antelope, the caracal and steppe wild sheep (Trans Caspian Urial ). Furthermore, various reptiles and rodents species live on the plateau. The gently undulating soil structure also offers a variety of birds of prey hunting grounds, such as the Turkoman Eagle Owl, the Würgfalken or the black vulture. The Ustyurt plateau once Headquartered Asian cheetahs (Acinonyx jubatus raddei, lives only in Iran and is acutely threatened with extinction ) and various subspecies of goiter gazelle. Due to the climatic changes caused by the Amu Darya water drainage from the Syr Darya and for the irrigation of cotton monoculture in Uzbekistan also the flora and fauna has changed the Ustyurt plateau. The accurate inventory of each species is largely unknown because the plateau is secluded and no roads or railway lines are present. A significant reserve on the southern edge of the plateau is the Kaplankyr Nature Reserve in Turkmenistan. A mansion in Kazakhstan part of Ustyurt Plateau is also a national nature reserve.