Topography of Iran with the Zāgros Mountains
|Highest peak||Dena ()|
|location||Iran , e.g. T. Iraq|
The Zāgros Mountains , also Sagros ( Persian رشتهکوههای زاگرس Reschte-Kuhhaye Zāgros ; Kurdish Çiyayên Zagrosê ; luric كۆیەل زاگرۥۇس), is the largest mountain range in modern-day Iran , with smaller parts also being on the territory of Iraq and the autonomous region of Kurdistan . It is part of the Alpidic mountain system . The highest point of the Zāgros is the summit of Qash Mastan ( Persian قاش مستان Qāsch Mastān ) or Bizhan 3 ( Persian بیژن ٣ Bīzhan Se ) in the Dena chain.
The Zāgros stretches for about 1500 km from the province of Kordestān on the Iraqi border to the Strait of Hormuz , where the Middle East and the Arabian Peninsula approach each other for 50 km. The mountains run roughly parallel to the alluvial land of the Tigris and the Persian Gulf at a distance of 50–100 km and are 200 to 300 km wide in several mountain ranges .
The Zagros Mountains were formed by the collision of two continental plates - the Eurasian and the Arabian plate - during the Alpidic orogeny . Current GPS measurements in Iran have shown that this collision is still active. The resulting deformation is not evenly distributed in Iran, but mainly found in the great mountain ranges of the Elbe and the Zagros.
A relatively dense GPS-supported network, which covers the Zagros in the Iranian part, also proves a high deformation within the Zagros. The measurements show that the current rate of shortening in the southeastern part of the Zagros is ~ 10 mm / a and in the northwestern part ~ 5 mm / a. These two zones of different deformations are separated by the Kazerun fault . The GPS results also indicate various foreshortening directions along the mountain range, i.e. H. normal shortening in the southeast and oblique shortening in northwestern Zagros.
The sediment cover of the Zagros lies in the southeast on a layer of rock salt , while in the northwest there is no or only a very thin layer of salt. The salt shears off . This different basal shear means that there are different topographies on both sides of the Kazerun Fault . In the northwest, the terrain is higher and less deformed, whereas the opposite is the case in the southeast.
Tensions in the earth's crust from the collision caused extensive folding of the existing layered sedimentary rocks. Subsequent erosion removed soft rocks such as mudstone and siltstone . Harder rocks such as limestone ( calcium-rich rock, consisting of the remains of marine organisms) and dolomite (rocks similar to limestone, contains calcium and magnesium ) remained. This differential erosion formed the straight ridges of the Zagros Mountains.
Salt domes and salt glaciers are a common feature of the mountains. Salt domes are an important target for oil exploration because natural gas often accumulates in their vicinity, always beneath impermeable layers of earth, and oil underneath .
The mountains are divided into many parallel mountain ranges (up to 10 or 250 km wide) and are the same age as the Alps. The main oil fields of Iran are in the western central foothills of the Zagros Mountains. The southern areas of Fars Province have slightly lower peaks (up to 4000 meters). They contain some limestone rocks with abundant marine fossils .
The Kuhrud Mountains form one of the parallel mountain ranges 300 km east of the Zagros. The area between these two imposing mountain ranges is home to a large population who live in the valleys in between. The valleys are quite high and have a temperate climate. The inland rivers , which flow into huge salt lakes , ensure a pleasant climate on the plateaus around Shiraz and Isfahan.
Paleogeography and prehistoric climate in south-east Iran: East Zagros during the Ice Age
The massifs of East Zagros, the Kuh-i-Jupar (29 ° 40 '- 30 ° 15'N, 56 ° 50' - 57 ° 35'E, 4135 m above sea level), Kuh-i-Lalezar ( 4374 m) and Kuh-i-Hezar (4469 m), which have no glaciers today, were up to 1900 m above sea level during an older ice age ( Riss ice age or pre-LGP = pre-last glacial period). M. down and during the last ice age ( Würm glaciation or LGP) up to a maximum of 2160 m above sea level. M. glaciated down. This resulted in z. B. on the north side of the Kuh-i-Jupar an approx. 20 km wide foreland glacier, which has been fed by a 17 km long valley to foreland glacier. The valley glacier thickness reached 350 to 550 m. The glacier snow line (ELA), as the height limit between the glacier nutrient area and the melting zone, was lowered by an average of 1590 (older glaciation) and 1490 (younger glaciation) vertical meters. Under the condition of comparable precipitation conditions, this would result in an ice age lowering of the annual mean temperature of 11.2 ° C for the Riss and 10.5 ° C for the Würm glaciation compared to today. It was probably drier and therefore colder.
History and culture
The Agriculture v in the Zagros Mountains since the 10th millennium. Demonstrable. It is believed that man first domesticated goats in the Zagros Mountains . Peoples like the Bakhtiari, Qashquai , Kurds and Luri have been populating the Zagros Mountains for several millennia and have survived there, among others. a. as nomadic shepherds. Other important archaeological sites are Jarmo and the Shanidar Caves in the Iraqi part. The places Hajji Firuz Tepe and Godin Tepe show that in the period between 5400 and 3500 BC Was operated in Zagros viticulture . The oldest cities in Zagros are Anschan and Susa .
In antiquity, the inhabitants of the Zagros Mountains are known through archaeological finds and Sumerian or Akkadian sources. Lulubi and Guteans invaded Mesopotamia, the Kassites immigrated and established a long-lived dynasty in Babylonia. In Assyrian times, the kingdoms Ellipi , Namri , Zamua , Parsua and Karalla were located here . The mountains often formed the border between empires such as the Roman Empire or Byzantine Empire and the Parthian Empire or Sassanid Empire and between the Safavids and the Ottoman Empire .
Other mountains in Iran
The somewhat shorter Kuhrud Mountains run roughly parallel to the Zagros - eastwards towards the large inland deserts . In northern Iran, within sight of the capital Tehran at 1600 m , between the deserts and the Kaspi provinces, lies the Elburs Mountains ( Damavand 5604 m).
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