64-491: Southern Iran consists of the southern mountain ranges of Zagros and Central Iranian Range , Khuzestan Plain and the northern coasts of Persian Gulf and Strait of Hormuz . It includes the provinces of Fars , Kohgiluyeh and Buyer Ahmad , Hormozgan and Bushehr . Sometimes Khuzestan and Kerman are also included in this region. The major cities in the region are Shiraz , Bandarabbas , Bushehr , Marvdasht , Jahrom , Yasuj , Fasa and Borazjan . The south of Iran
128-513: 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
192-674: 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
256-405: A fault as oblique requires both dip and strike components to be measurable and significant. Some oblique faults occur within transtensional and transpressional regimes, and others occur where the direction of extension or shortening changes during the deformation but the earlier formed faults remain active. The hade angle is defined as the complement of the dip angle; it is the angle between
320-582: A fault hosting valuable porphyry copper deposits is northern Chile's Domeyko Fault with deposits at Chuquicamata , Collahuasi , El Abra , El Salvador , La Escondida and Potrerillos . Further south in Chile Los Bronces and El Teniente porphyry copper deposit lie each at the intersection of two fault systems. Faults may not always act as conduits to surface. It has been proposed that deep-seated "misoriented" faults may instead be zones where magmas forming porphyry copper stagnate achieving
384-489: A fault plane, where it becomes locked, are called asperities . Stress builds up when a fault is locked, and when it reaches a level that exceeds the strength threshold, the fault ruptures and the accumulated strain energy is released in part as seismic waves , forming an earthquake . Strain occurs accumulatively or instantaneously, depending on the liquid state of the rock; the ductile lower crust and mantle accumulate deformation gradually via shearing , whereas
448-408: A fault's age by studying soil features seen in shallow excavations and geomorphology seen in aerial photographs. Subsurface clues include shears and their relationships to carbonate nodules , eroded clay, and iron oxide mineralization, in the case of older soil, and lack of such signs in the case of younger soil. Radiocarbon dating of organic material buried next to or over a fault shear
512-427: A hanging wall or foot wall where a thrust fault formed along a relatively weak bedding plane is known as a flat and a section where the thrust fault cut upward through the stratigraphic sequence is known as a ramp . Typically, thrust faults move within formations by forming flats and climbing up sections with ramps. This results in the hanging wall flat (or a portion thereof) lying atop the foot wall ramp as shown in
576-484: A major fault. Synthetic faults dip in the same direction as the major fault while the antithetic faults dip in the opposite direction. These faults may be accompanied by rollover anticlines (e.g. the Niger Delta Structural Style). All faults have a measurable thickness, made up of deformed rock characteristic of the level in the crust where the faulting happened, of the rock types affected by
640-400: A manner that creates multiple listric faults. The fault panes of listric faults can further flatten and evolve into a horizontal or near-horizontal plane, where slip progresses horizontally along a decollement . Extensional decollements can grow to great dimensions and form detachment faults , which are low-angle normal faults with regional tectonic significance. Due to the curvature of
704-421: A non-vertical fault are known as the hanging wall and footwall . The hanging wall occurs above the fault plane and the footwall occurs below it. This terminology comes from mining: when working a tabular ore body, the miner stood with the footwall under his feet and with the hanging wall above him. These terms are important for distinguishing different dip-slip fault types: reverse faults and normal faults. In
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#1732765467144768-464: A reverse fault, the hanging wall displaces upward, while in a normal fault the hanging wall displaces downward. Distinguishing between these two fault types is important for determining the stress regime of the fault movement. Faults are mainly classified in terms of the angle that the fault plane makes with the Earth's surface, known as the dip , and the direction of slip along the fault plane. Based on
832-451: A volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth 's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults . Energy release associated with rapid movement on active faults is
896-422: Is a horst . A sequence of grabens and horsts on the surface of the Earth produces a characteristic basin and range topography . Normal faults can evolve into listric faults, with their plane dip being steeper near the surface, then shallower with increased depth, with the fault plane curving into the Earth. They can also form where the hanging wall is absent (such as on a cliff), where the footwall may slump in
960-423: Is a zone of folding close to a fault that likely arises from frictional resistance to movement on the fault. The direction and magnitude of heave and throw can be measured only by finding common intersection points on either side of the fault (called a piercing point ). In practice, it is usually only possible to find the slip direction of faults, and an approximation of the heave and throw vector. The two sides of
1024-701: 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
1088-544: Is defined by the direction of movement of the ground as would be seen by an observer on the opposite side of the fault. A special class of strike-slip fault is the transform fault when it forms a plate boundary. This class is related to an offset in a spreading center , such as a mid-ocean ridge , or, less common, within continental lithosphere , such as the Dead Sea Transform in the Middle East or
1152-543: Is often critical in distinguishing active from inactive faults. From such relationships, paleoseismologists can estimate the sizes of past earthquakes over the past several hundred years, and develop rough projections of future fault activity. Many ore deposits lie on or are associated with faults. This is because the fractured rock associated with fault zones allow for magma ascent or the circulation of mineral-bearing fluids. Intersections of near-vertical faults are often locations of significant ore deposits. An example of
1216-492: Is particularly clear in the case of detachment faults and major thrust faults . The main types of fault rock include: In geotechnical engineering , a fault often forms a discontinuity that may have a large influence on the mechanical behavior (strength, deformation, etc.) of soil and rock masses in, for example, tunnel , foundation , or slope construction. The level of a fault's activity can be critical for (1) locating buildings, tanks, and pipelines and (2) assessing
1280-567: Is still active and the resulting deformation is distributed non-uniformly in the country, mainly taken up in 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
1344-455: Is very diverse in terms of ethnicity, which includes Persians (including Kohmera, Basri, Etchmi, etc.) includes Arabs and Iranians of African origin. Also, minorities from many ethnic groups of Iranian descent have migrated to this region from different regions of Iran for various reasons, including work reasons; Among these immigrants, we can mention Azerbaijanis , Mazandaranis , Gilaks , Talysh , Tats Kurds , Lurs ، who migrated from
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#17327654671441408-762: The Alpine Fault in New Zealand. Transform faults are also referred to as "conservative" plate boundaries since the lithosphere is neither created nor destroyed. Dip-slip faults can be either normal (" extensional ") or reverse . The terminology of "normal" and "reverse" comes from coal mining in England, where normal faults are the most common. With the passage of time, a regional reversal between tensional and compressional stresses (or vice-versa) might occur, and faults may be reactivated with their relative block movement inverted in opposite directions to
1472-695: The Arabian Plate . This collision mainly happened during 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
1536-766: 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
1600-562: 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
1664-689: 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
1728-643: 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,
1792-585: 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
1856-566: The continental arc collision in the Eocene (56–34 mya) both had major effects on uplifts in 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
1920-500: 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
1984-657: The seismic shaking and tsunami hazard to infrastructure and people in the vicinity. In California, for example, new building construction has been prohibited directly on or near faults that have moved within the Holocene Epoch (the last 11,700 years) of the Earth's geological history. Also, faults that have shown movement during the Holocene plus Pleistocene Epochs (the last 2.6 million years) may receive consideration, especially for critical structures such as power plants, dams, hospitals, and schools. Geologists assess
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2048-550: 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
2112-650: 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
2176-569: The SE Zagros is deforming above 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
2240-507: The SE, deformation was spread more and 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
2304-652: 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
2368-545: 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
2432-530: 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
2496-454: 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
2560-403: The brittle upper crust reacts by fracture – instantaneous stress release – resulting in motion along the fault. A fault in ductile rocks can also release instantaneously when the strain rate is too great. Slip is defined as the relative movement of geological features present on either side of a fault plane. A fault's sense of slip is defined as the relative motion of the rock on each side of
2624-422: The cause of most earthquakes . Faults may also displace slowly, by aseismic creep . A fault plane is the plane that represents the fracture surface of a fault. A fault trace or fault line is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. A fault zone is a cluster of parallel faults. However,
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2688-615: 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
2752-436: The direction of slip, faults can be categorized as: In a strike-slip fault (also known as a wrench fault , tear fault or transcurrent fault ), the fault surface (plane) is usually near vertical, and the footwall moves laterally either left or right with very little vertical motion. Strike-slip faults with left-lateral motion are also known as sinistral faults and those with right-lateral motion as dextral faults. Each
2816-473: 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. Strike-slip fault In geology , a fault is a planar fracture or discontinuity in
2880-456: The fault and of the presence and nature of any mineralising fluids . Fault rocks are classified by their textures and the implied mechanism of deformation. A fault that passes through different levels of the lithosphere will have many different types of fault rock developed along its surface. Continued dip-slip displacement tends to juxtapose fault rocks characteristic of different crustal levels, with varying degrees of overprinting. This effect
2944-402: The fault concerning the other side. In measuring the horizontal or vertical separation, the throw of the fault is the vertical component of the separation and the heave of the fault is the horizontal component, as in "Throw up and heave out". The vector of slip can be qualitatively assessed by studying any drag folding of strata, which may be visible on either side of the fault. Drag folding
3008-576: The fault plane and a vertical plane that strikes parallel to the fault. Ring faults , also known as caldera faults , are faults that occur within collapsed volcanic calderas and the sites of bolide strikes, such as the Chesapeake Bay impact crater . Ring faults are the result of a series of overlapping normal faults, forming a circular outline. Fractures created by ring faults may be filled by ring dikes . Synthetic and antithetic are terms used to describe minor faults associated with
3072-401: The fault plane, the horizontal extensional displacement on a listric fault implies a geometric "gap" between the hanging and footwalls of the fault forms when the slip motion occurs. To accommodate into the geometric gap, and depending on its rheology , the hanging wall might fold and slide downwards into the gap and produce rollover folding , or break into further faults and blocks which fil in
3136-427: The fault-bend fold diagram. Thrust faults form nappes and klippen in the large thrust belts. Subduction zones are a special class of thrusts that form the largest faults on Earth and give rise to the largest earthquakes. A fault which has a component of dip-slip and a component of strike-slip is termed an oblique-slip fault . Nearly all faults have some component of both dip-slip and strike-slip; hence, defining
3200-506: 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
3264-515: 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
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#17327654671443328-475: The gap. If faults form, imbrication fans or domino faulting may form. A reverse fault is the opposite of a normal fault—the hanging wall moves up relative to the footwall. Reverse faults indicate compressive shortening of the crust. A thrust fault has the same sense of motion as a reverse fault, but with the dip of the fault plane at less than 45°. Thrust faults typically form ramps, flats and fault-bend (hanging wall and footwall) folds. A section of
3392-448: 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
3456-449: The northwest Zagros. The north–south Kazerun strike-slip fault divides 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
3520-439: The northwest, north, west and center of Iran to the south of Iran. Zagros 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,
3584-500: The original movement (fault inversion). In such a way, a normal fault may therefore become a reverse fault and vice versa. In a normal fault, the hanging wall moves downward, relative to the footwall. The dip of most normal faults is at least 60 degrees but some normal faults dip at less than 45 degrees. A downthrown block between two normal faults dipping towards each other is a graben . A block stranded between two grabens, and therefore two normal faults dipping away from each other,
3648-416: 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
3712-652: The range continues southeast to the waters of 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
3776-418: 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
3840-412: The right time for—and type of— igneous differentiation . At a given time differentiated magmas would burst violently out of the fault-traps and head to shallower places in the crust where porphyry copper deposits would be formed. As faults are zones of weakness, they facilitate the interaction of water with the surrounding rock and enhance chemical weathering . The enhanced chemical weathering increases
3904-468: The term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the distinction, as the rock between the faults is converted to fault-bound lenses of rock and then progressively crushed. Due to friction and the rigidity of the constituent rocks, the two sides of a fault cannot always glide or flow past each other easily, and so occasionally all movement stops. The regions of higher friction along
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#17327654671443968-438: 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
4032-530: 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
4096-410: 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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