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58-448: The Zagros Mountains are a long mountain range in Iran , northern Iraq , and southeastern Turkey . The mountain range has a total length of 1,600 km (990 miles). The Zagros range begins in northwestern Iran and roughly follows Iran's western border while covering much of southeastern Turkey and northeastern Iraq. From this border region, the range continues southeast to the waters of

116-513: A Lur tribe from Iran , primarily inhabiting the Central and South Zagros. Major cities inhabited by Bakhtiaris include Masjed Soleyman , Izeh and Shahr-e Kord . A significant number of Bakhtiari still practice nomadic pastoralism. Kurds are another Iranic group found in the northwestern and the eastern Zagros Taurus mountain ranges , which spans southeastern Turkey, northwestern Iran, northern Iraq, and northern Syria. The high altitude of

174-673: A common feature of the Zagros Mountains. Salt domes are an important target for petroleum exploration , as the impermeable salt frequently traps petroleum beneath other rock layers. There is also much water-soluble gypsum in the region. The mountains are completely of sedimentary origin and are made primarily of limestone . In the Elevated Zagros or the Higher Zagros, the Paleozoic rocks can be found mainly in

232-566: A layer of rock salt (acting as a ductile decollement with a low basal friction ), whereas in the NW Zagros the salt layer is missing or is very thin. This different basal friction is partly responsible for the different topographies on either side of the Kazerun fault. Higher topography and narrower zone of deformation in the NW Zagros is observed whereas in the SE, deformation was spread more and

290-470: A wider zone of deformation with lower topography was formed. Stresses induced in the Earth's crust by the collision caused extensive folding of the preexisting layered sedimentary rocks . Subsequent erosion removed softer rocks, such as mudstone (rock formed by consolidated mud) and siltstone (a slightly coarser-grained mudstone) while leaving harder rocks, such as limestone (calcium-rich rock consisting of

348-427: Is a type of structural dome formed when salt (or other evaporite minerals) intrudes into overlying rocks in a process known as diapirism . Salt domes can have unique surface and subsurface structures, and they can be discovered using techniques such as seismic reflection . They are important in petroleum geology as they can function as petroleum traps . Stratigraphically, salt basins developed periodically from

406-701: Is also home to populations of Assyrians , Turkic peoples and Farsi speaking Iranians . The mountains contain several ecosystems . Prominent among them are the forest and forest steppe areas with a semi-arid climate . As defined by the World Wildlife Fund and used in their Wildfinder, the particular terrestrial ecoregion of the mid to high mountain area is Zagros Mountains forest steppe (PA0446). The annual precipitation ranges from 400–800 mm (16–31 in) and falls mostly in winter and spring. Winters are severe, with low temperatures often below −25 °C (−13 °F). The region exemplifies

464-538: Is at work while the mountains are being uplifted until the mountains are reduced to low hills and plains. The early Cenozoic uplift of the Rocky Mountains of Colorado provides an example. As the uplift was occurring some 10,000 feet (3,000 m) of mostly Mesozoic sedimentary strata were removed by erosion over the core of the mountain range and spread as sand and clays across the Great Plains to

522-599: Is home to most of the US Strategic Petroleum Reserve . Avery Island was formed by a salt dome. During the break-up of the south Atlantic, Aptian (Lower Cretaceous) age salt was deposited within the area of thinned crust on both the Brazilian and conjugate Angola/Gabon margins forming many salt domes. During the Messinian salinity crisis ( Late Miocene ), thick salt layers were formed as

580-439: Is recognized that a single evaporation event is rarely enough to produce the vast quantities of salt needed to form a layer thick enough for the formation of salt diapirs , indicating that a sustained period of episodic flooding and evaporation of the basin must occur. Over time, the layer of salt is covered with deposited sediment , becoming buried under an increasingly large overburden . Previously, researchers believed that

638-865: The Alpide belt . The Pacific Ring of Fire includes the Andes of South America, extends through the North American Cordillera , the Aleutian Range , on through Kamchatka Peninsula , Japan , Taiwan , the Philippines , Papua New Guinea , to New Zealand . The Andes is 7,000 kilometres (4,350 mi) long and is often considered the world's longest mountain system. The Alpide belt stretches 15,000 km across southern Eurasia , from Java in Maritime Southeast Asia to

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696-551: The Annamite Range . If the definition of a mountain range is stretched to include underwater mountains, then the Ocean Ridge forms the longest continuous mountain system on Earth, with a length of 65,000 kilometres (40,400 mi). The position of mountain ranges influences climate, such as rain or snow. When air masses move up and over mountains, the air cools, producing orographic precipitation (rain or snow). As

754-818: The Fars Province have somewhat lower summits, reaching 4,000 metres (13,000 feet). They contain some limestone rocks showing abundant marine fossils. The peaks that are at least 3800 meters high and have a topographic prominence of at least 300 meters: The Zagros Mountains have significant ancient history. They were occupied by early humans since the Lower Paleolithic Period. The earliest human fossils discovered in Zagros belongs to Neanderthals and come from Shanidar Cave , Bisitun Cave , and Wezmeh Cave. The remains of ten Neanderthals , dating from around 65,000–35,000 years ago, have been found in

812-804: The Iberian Peninsula in Western Europe , including the ranges of the Himalayas , Karakoram , Hindu Kush , Alborz , Caucasus , and the Alps . The Himalayas contain the highest mountains in the world, including Mount Everest , which is 8,848 metres (29,029 ft) high. Mountain ranges outside these two systems include the Arctic Cordillera , Appalachians , Great Dividing Range , East Siberians , Altais , Scandinavians , Qinling , Western Ghats , Vindhyas , Byrrangas , and

870-722: The Miocene (about 25–5 mya or million years ago ) and folded the entirety of the rocks that had been deposited from the Paleozoic (541–242 mya) to the Cenozoic (66 mya – present) in the passive continental margin on the Arabian Plate. However, the obduction of Neotethys oceanic crust during the Cretaceous (145–66 mya), and the continental arc collision in the Eocene (56–34 mya) both had major effects on uplifts in

928-559: The Mithrim Montes and Doom Mons on Titan, and Tenzing Montes and Hillary Montes on Pluto. Some terrestrial planets other than Earth also exhibit rocky mountain ranges, such as Maxwell Montes on Venus taller than any on Earth and Tartarus Montes on Mars . Jupiter's moon Io has mountain ranges formed from tectonic processes including the Boösaule , Dorian, Hi'iaka and Euboea Montes . Salt dome A salt dome

986-560: The Neolithic period . The DNA from this bone fragment shows that it is from a distinct genetic group, which was not known to scientists before. He belongs to the Y-DNA haplogroup G2b, specifically its branch G-Y37100 , and mitochondrial haplogroup J1d6. He had brown eyes, relatively dark skin, and black hair, although Neolithic pre Indo-European Iranians carried reduced pigmentation-associated alleles in several genes and derived alleles at 7 of

1044-638: The Paleogene (66–23 mya) rocks south of the Cretaceous rocks and then the Neogene (23–2.6 mya) rocks south of the Paleogene rocks. The mountains are divided into many parallel sub-ranges (up to 10 or 250 km (6.2 or 155.3 miles) wide), and orogenically have the same age as the Alps . Iran's main oilfields lie in the western central foothills of the Zagros mountain range. The southern ranges of

1102-587: The Paradox Formation forms salt domes throughout the Paradox Basin in the US, which extends from eastern Utah , through southwestern Colorado into northwestern New Mexico . An example of an emergent salt dome is at Onion Creek, Utah / Fisher Towers near Moab, Utah. A Paradox Formation salt body that has risen as a ridge through several hundred meters of overburden, predominantly sandstone . As

1160-726: The Persian Gulf . It spans the southern parts of the Armenian highlands , and the whole length of the western and southwestern Iranian plateau , ending at the Strait of Hormuz . The highest point is Mount Dena , at 4,409 metres (14,465 ft). The Zagros fold and thrust belt was mainly formed by the collision of two tectonic plates , the Eurasian Plate and the Arabian Plate . This collision mainly happened during

1218-466: The Proterozoic to the Neogene . The formation of a salt dome begins with the deposition of salt in a restricted basin . In these basins, the outflow of water exceeds inflow. Specifically, the basin loses water through evaporation , resulting in the precipitation and deposition of salt. While the rate of sedimentation of salt is significantly larger than the rate of sedimentation of clastics , it

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1276-642: The Sumerian , Akkadian and Assyrian cities of Mesopotamia . The mountains create a geographic barrier between the Mesopotamian Plain, which is in modern Iraq , and the Iranian plateau . A small archive of clay tablets detailing the complex interactions of these groups in the early second millennium BC has been found at Tell Shemshara along the Little Zab . Tell Bazmusian , near Shemshara,

1334-585: The Zagros Mountains mouse-like hamster ( Calomyscus bailwardi ), the Basra reed-warbler ( Acrocephalus griseldis ) and the striped hyena ( Hyena hyena ). The Persian fallow deer ( Dama dama mesopotamica ), an ancient domesticate once thought extinct, was rediscovered in the late 20th century in Khuzestan Province, in the southern Zagros. Also, wild goats can be found almost all over

1392-497: The pet trade and habitat destruction . Climate change is predicted to strongly impact this species. The entrance to the ancient Mesopotamian underworld was believed to be located in the Zagros Mountains in the far east. A staircase led down to the gates of the underworld. The underworld itself is usually located even deeper below ground than the Abzu , the body of freshwater which the ancient Mesopotamians believed lay deep beneath

1450-549: The 12 loci, showing the strongest signatures of selection in ancient Eurasians. He did not contribute to the genetic makeup of early European farmers or modern Europeans . Instead, he was the most genetically similar to modern Iranian Zoroastrians , followed by Fars , Balochi , Brahui , Kalash and Georgians . Gallego-Llorente et al. (2016) believes that the Zagros Mountain was a plausible source of Eurasian ancestry in Central and South Asia, along with Kotias , which

1508-650: The Last Glacial Period they had been glaciated to a depth in excess of 1,900 metres (1.2 miles), and during the Last Glacial Period to a depth in excess of 2,160 metres (7,090 feet). Evidence exists of a 20 km (12 miles) wide glacier fed along a 17 km (11 miles) long valley dropping approximately 1,600 m (5,200 ft) along its length on the north side of Kuh-i-Jupar with a thickness of 350–550 m (1,150–1,800 ft). Under conditions of precipitation comparable to current climatic record-keeping, this size of glacier could be expected to form where

1566-649: The Shanidar Cave. The cave also contains two later " proto-Neolithic " cemeteries, one of which dates back about 10,600 years and contains 35 individuals. Evidence from later Upper Paleolithic and Epipaleolithic occupations come from Yafteh Cave, Kaldar Cave near Khoramabad , and Warwasi , Malaverd near Kermanshah , Kenacheh Cave in Kurdistan, Boof Cave in Fars and a number of other caves and rock shelters. Signs of early agriculture date back as far as 9000 BC in

1624-560: The United States. Several countries use solution mining to form caverns for holding large amounts of oil or gas reserves . The caprock above the salt domes can contain deposits of native sulfur (recovered by the Frasch process ). They can also contain deposits of metals, sodium salts , nitrates , and other substances, which can be used in products such as table salt and chemical de-icers . Salt domes occur in many parts of

1682-462: The Zagros into two distinct zones of deformation. The GPS results also show different shortening directions along the belt, normal shortening in the southeast, and oblique shortening in the northwest Zagros. The Zagros mountains were created around the time of the second ice age, which caused the tectonic collision, leading to its uniqueness. The sedimentary cover in the SE Zagros is deforming above

1740-543: The Zagros mountain range. In the late 19th century, the Asiatic lion ( Panthera leo persica ) inhabited the southwestern part of the mountains. It is now extinct in this region. The Luristan newt ( Neurergus kaiseri ) is a salamander endemic to a small section of the central Zagros Mountains in Iran. It lives in highland streams and is primarily aquatic. This newt is considered vulnerable to extinction due to poaching for

1798-528: The Zagros mountains produces a series of choke points and valleys perfect for agriculture and human development. It has also long defended the Kurds in times of war by acting as a natural barrier . Qashqai people are a tribal confederation in Iran mostly of Turkic origin. Significant populations can be found in Central and South Zagros, especially around the city of Shiraz in the Fars province . The Zagros

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1856-402: The accumulation of sediments around the diapir contribute to its growth and eventually form into a dome. Some salt domes can be seen from Earth's surface. They can also be located by finding unique surface structures and surrounding phenomena. For instance, salt domes can contain or be near sulfur springs and natural gas vents . Some salt domes have salt sheets that extrude from the top of

1914-627: The air descends on the leeward side, it warms again (following the adiabatic lapse rate ) and is drier, having been stripped of much of its moisture. Often, a rain shadow will affect the leeward side of a range. As a consequence, large mountain ranges, such as the Andes, compartmentalize continents into distinct climate regions . Mountain ranges are constantly subjected to erosional forces which work to tear them down. The basins adjacent to an eroding mountain range are then filled with sediments that are buried and turned into sedimentary rock . Erosion

1972-450: The annual average temperature was between 10.5 and 11.2 °C (50.9 and 52.2 °F), but since conditions are expected to have been dryer during the period in which this glacier was formed, the temperature must have been lower. Although currently degraded through overgrazing and deforestation , the Zagros region is home to a rich and complex flora. Remnants of the originally widespread oak -dominated woodland can still be found, as can

2030-529: The central and southern North Sea , extending eastwards into Germany. Upper Triassic salt forms salt domes in the Essaouira Basin onshore and offshore Morocco. An equivalent salt sequence, the Argo Formation, is associated with salt dome formation on the conjugate Nova Scotia margin . The Gulf Coast is home to over 500 salt domes formed from Middle Jurassic Louann Salt . This region

2088-509: The compaction of overlying sediment and subsequent decrease in buoyancy led to salt rising and intruding into the overburden due to its ductility , thereby creating a salt diapir. However, after the 1980s, the primary force that drives the flow of salt is considered to be differential loading. Differential loading can be caused by gravitational forces ( gravitational loading ), forced displacement of salt boundaries ( displacement loading ), or thermal gradients ( thermal loading ). The flow of

2146-614: The continental variation of the Mediterranean climate pattern, with a snowy winter and mild, rainy spring, followed by a dry summer and autumn. The mountains of the East-Zagros, the Kuh-i-Jupar (4,135 m (13,566 ft)), Kuh-i-Lalezar (4,374 m (14,350 ft)) and Kuh-i-Hezar (4,469 m (14,662 ft)) do not currently have glaciers. Only at Zard Kuh and Dena some glaciers still survive. However, before

2204-409: The dome, forming pockets and reservoirs of petroleum and natural gas (known as petroleum traps) . In 1901, an exploratory oil well was drilled into Spindletop Hill near Beaumont , Texas. This led to the discovery of the first salt dome, revealed the importance of salt to the formation of hydrocarbon accumulations, and produced enough oil for petroleum to become an economically feasible fuel for

2262-508: The dome; these are referred to as salt plugs. These plugs can coalesce to form salt canopies, which can then be remobilized by roof sedimentation, with the most prominent example in the northern Gulf of Mexico basin . Another structure that can form from salt domes are salt welds . These occur when the growth of a dome is prevented by an exhausted supply of salt, and the top and bottom contacts merge. Salt domes have also been located using seismic refraction and seismic reflection . The latter

2320-520: The earth. The region was influenced by Mesopotamian and Hurrian religion in the Bronze and Iron Ages, and later by Zoroastrianism and Syriac Christianity . Today the vast majority of the population are Iranic and Turkic Muslims , with small numbers of Christians , mainly Assyrians and Armenians also extant. Mountain range Mountain ranges are usually segmented by highlands or mountain passes and valleys . Individual mountains within

2378-485: The east. This mass of rock was removed as the range was actively undergoing uplift. The removal of such a mass from the core of the range most likely caused further uplift as the region adjusted isostatically in response to the removed weight. Rivers are traditionally believed to be the principal cause of mountain range erosion, by cutting into bedrock and transporting sediment. Computer simulation has shown that as mountain belts change from tectonically active to inactive,

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2436-437: The expansion of offshore petroleum exploration efforts led to the discovery of numerous salt domes soon after World War II . Salt domes are the site of many of the world's hydrocarbon provinces. The rock salt of the salt dome is mostly impermeable, so, as it moves up towards the surface, it penetrates and bends existing rock along with it. As strata of rock are penetrated, they are, generally, bent upwards where they meet

2494-506: The foothills of the Zagros mountains, including Sulaymaniyah , Kermanshah , Khorramabad , and Shiraz . The Lurs are an Iranic tribe, primarily inhabiting the Central, Western, and Southern Zagros. Cities inhibited by Lurs include Khorramabad , Borujerd , Malayer , Izeh , Shahr-e Kord , Yasuj . Lurs speak Luri and span across many provinces in Iran including Lorestan , Khuzestan , Chaharmahal and Bakthiari , Ilam , Kohgiluyeh and Boyer-Ahmad , and Hamedan . The Bakhtiaris are

2552-513: The foothills of the mountains. Some settlements later grew into cities, eventually named Anshan and Susa ; Jarmo is one archaeological site in this area. Some of the earliest evidence of wine production has been discovered in the mountains; both the settlements of Hajji Firuz Tepe and Godin Tepe have given evidence of wine storage dating between 3500 and 5400 BC. A human metatarsal bone fragment from Wezmeh Cave has been analyzed and dated to

2610-479: The major mountain belts like Alborz and Zagros. A relatively dense GPS network which covered the Iranian Zagros also proves a high rate of deformation within the Zagros. The GPS results show that the current rate of shortening in the southeast Zagros is ~10 mm/a (0.39 in/year), dropping to ~5 mm/a (0.20 in/year) in the northwest Zagros. The north–south Kazerun strike-slip fault divides

2668-447: The mountain range include: Allium iranicum , Astragalus crenophila , Bellevalia kurdistanica , Cousinia carduchorum , Cousinia odontolepis , Echinops rectangularis , Erysimum boissieri , Iris barnumiae , Ornithogalum iraqense , Scrophularia atroglandulosa , Scorzonera kurdistanica , Tragopogon rechingeri , and Tulipa kurdica . The Zagros are home to many threatened and endangered species, including

2726-476: The northeastern parts of the belt. The process of collision continues to the present, and as the Arabian Plate is being pushed against the Eurasian Plate, the Zagros Mountains and the Iranian plateau are getting higher and higher. Recent GPS measurements in Iran have shown that this collision is still active and the resulting deformation is distributed non-uniformly in the country, mainly taken up in

2784-414: The park-like pistachio / almond steppelands. The ancestors of many familiar foods, including wheat, barley , lentil , almond, walnut , pistachio, apricot , plum , pomegranate and grape can be found growing wild throughout the mountains. Quercus brantii (covering more than 50% of the Zagros forest area) is the most important tree species of the Zagros in Iran. Other floral endemics found within

2842-627: The rate of erosion drops because there are fewer abrasive particles in the water and fewer landslides. Mountains on other planets and natural satellites of the Solar System, including the Moon , are often isolated and formed mainly by processes such as impacts, though there are examples of mountain ranges (or "Montes") somewhat similar to those on Earth. Saturn 's moon Titan and Pluto , in particular, exhibit large mountain ranges in chains composed mainly of ices rather than rock. Examples include

2900-418: The remains of marine organisms) and dolomite (rocks similar to limestone containing calcium and magnesium ). This differential erosion formed the linear ridges of the Zagros Mountains. The depositional environment and tectonic history of the rocks were conducive to the formation and trapping of petroleum, and the Zagros region is an important area for oil production. Salt domes and salt glaciers are

2958-553: The salt body rose, the overburden formed an anticline (arching upward along its center line) which fractured and eroded to expose the salt body. Offshore northern Norway in the southwestern Barents Sea , thick Upper Carboniferous – Lower Permian salt was deposited, forming salt domes in the Hammerfest and Nordkapp basins. In northwest Europe Upper Permian salt of the Zechstein Group has formed salt domes over

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3016-425: The salt overcomes the strength of the overburden as well as boundary friction aided by overburden extension , erosion, thrust faults , ductile thinning, or other forms of regional deformation. The vertical growth of salt formations creates pressure on the upward surface, causing extension and faulting . Once the salt completely pierces the overburden, it can rise through a process known as passive diapirism where

3074-479: The same mountain range do not necessarily have the same geologic structure or petrology . They may be a mix of different orogenic expressions and terranes , for example thrust sheets , uplifted blocks , fold mountains, and volcanic landforms resulting in a variety of rock types . Most geologically young mountain ranges on the Earth's land surface are associated with either the Pacific Ring of Fire or

3132-438: The upper and higher sections of the peaks of the Zagros Mountains, along the Zagros main fault. On both sides of this fault, there are Mesozoic rocks, a combination of Triassic (252–201 mya) and Jurassic (201–145 mya) rocks that are surrounded by Cretaceous rocks on both sides. The Folded Zagros (the mountains south of the Elevated Zagros and almost parallel to the main Zagros fault) is formed mainly of Tertiary rocks, with

3190-749: The world where there is a sufficiently thick layer of rock salt developed. In the Middle East, the upper Neoproterozoic salt of the Hormuz Formation is associated with widespread salt dome formation in most parts of the Persian Gulf and onshore in Iran, Iraq, United Arab Emirates , and Oman . The thicker salt is found in a series of basins: the Western Gulf, the Southern Gulf, and the Oman salt basins. Pennsylvanian age salt of

3248-512: Was developed based on techniques from the former and is more effective. Seismic refraction uses seismic waves to characterize subsurface geologic conditions and structures. Seismic reflection highlights the presence of a stark density contrast between the salt and surrounding sediment. Seismic techniques are particularly effective as salt domes are typically depressed blocks of crust bordered by parallel normal faults ( graben ) that can be flanked by reverse faults. Advances in seismic reflection and

3306-529: Was inhabited by Caucasus Hunter-Gatherers. He cites archaeological evidence of eastward Neolithic expansions from the Near East. During early ancient times, the Zagros was the home of various Pre Indo-European peoples such as the Hurrians , Guti , Kassites , Elamites , Turukku and Lullubi , (together with Semitic peoples such as Assyrians and Amorites on the western side) who periodically invaded

3364-409: Was occupied between 5000 BCE and 800 CE, although not continuously. The Zagros mountains have been inhabited by different groups of pastoralists and farmers for thousands of years. Current Pastoralist groups such as Lurs , Bakhtiari Lurs , Kurds or Qashqais move from their herds from the east slopes in summer ( Yeylāgh ) to the west slopes in winter ( Gheshlāgh ). Some major cities are located on

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