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39-458: The Tortonian roughly overlaps with the regional Pannonian Stage of the Paratethys timescale of Central Europe. It also overlaps the upper Astaracian , Vallesian and lower Turolian European land mammal ages , the upper Clarendonian and lower Hemphillian North American land mammal ages and the upper Chasicoan and lower Huayquerian South American land mammal ages . The Tortonian

78-640: A brackish sea in the Pannonian Basin . Many of these would disappear before the start of the Pleistocene . At present, only the Black Sea , Caspian Sea and the Aral Sea remain of what was once a vast inland sea. Elburz The Alborz ( listen Persian : البرز ) range, also spelled as Alburz , Elburz or Elborz , is a mountain range in northern Iran that stretches from

117-680: A giant anoxic sea . The western and central Paratethys basins experienced intense tectonic activity and anoxia during the Oligocene and early Miocene and became filled with sediments . Local gypsum and salt evaporitic basins formed in the East Carpathian region during the early Miocene. The Eastern Paratethys basin, holding most of the water of Paratethys, remained anoxic for almost 20 million years (35–15 Mya), and during this time Paratethys acted as an enormous carbon sink trapping organic matter in its sediments. The Paratethys anoxia

156-459: A lesser extent, in the Pannonian depression in central Hungary . Some 12 million years ago, slightly before the onset of the late Miocene , the ancient sea transformed into a megalake that covered more than 2.8 million square kilometers, from the eastern Alps to what is now Kazakhstan , and characterized by salinities generally ranging between 12 and 14%. During its five-million-year lifetime,

195-636: Is located in the Central Alborz Mountains. Mount Damavand is the 12th most prominent peak in the world and the second most prominent in Asia after Mount Everest . The name Alborz is derived from Harā Barazaitī , a legendary mountain in the Avesta , the main text of Zoroastrianism . Harā Barazaitī is from a Proto-Iranian name, Harā Bṛzatī , meaning "Mountain Rampart." Bṛzatī is

234-638: Is lush and forested. The natural vegetation of this region grows in distinct zones: The wild cypress is the dominant form of vegetation in some valleys, while olive trees grow in the western valleys of the Central Alborz near the Sefidrud . The bezoar ibex , Blanford's fox , Rüppell's fox , red fox , Persian fallow deer , wild boar , Syrian brown bear , Persian leopard , Indian wolf , buzzard , goose , woodpecker , griffon vulture , and eagle are among important animals and birds found in

273-424: Is only 60–130 km wide and consists of sedimentary series dating from Upper Devonian to Oligocene , prevalently Jurassic limestone over a granite core. Continental conditions regarding sedimentation are reflected by thick Devonian sandstones and by Jurassic shales containing coal seams. Marine conditions are reflected by Carboniferous and Permian strata that are composed mainly of limestones. In

312-697: The Aral Sea in Central Asia . Paratethys was peculiar due to its paleogeography : it consisted of a series of deep basins, formed during the Oxfordian stage of the Late Jurassic as an extension of the rift that formed the Central Atlantic Ocean . These basins were connected with each other and the global ocean by narrow and shallow seaways that often limited water exchange and caused widespread long-term anoxia . Paratethys

351-693: The Caucasus Mountains and Mount Elbariz (Albariz, Jebal Barez ) in the Kerman area above the Strait of Hormuz . All these names reflect the same Iranian language compound, and have been speculatively identified, at one time or another, as the legendary mountain Hara Berezaiti of the Avesta . The Alborz mountain range forms a barrier between the south Caspian and the Iranian plateau . It

390-533: The Department of Paleolithic of the National Museum of Iran and ICHTO of Gilan . The presence of large numbers of cave bear and brown bear remains and sparse stone artifacts at the site indicates that Darband primarily represents a bear den. The co-occurrence of artifacts and bear bones does not imply human predation or scavenging. Because there are no clear cut marks, except a few burning signs on

429-762: The Iranian plate and their final collision, the Iranian plate was pressed from both sides. The collisions finally caused the folding of the Upper Paleozoic, Mesozoic , and Paleogene rocks and the Cenozoic (chiefly the Eocene ) volcanism , to form the Alborz Mountains, primarily during the Miocene . The Alpine orogeny began, therefore, with Eocene volcanism in southwestern and south-central parts of

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468-784: The Outer Carpathians , Transylvanian and Pannonian basins. Salt mines extract this middle-Miocene salt in Transylvania: Turda , Ocna Mures , Ocna Sibiului and Praid ; in the Eastern and Carpathians: Wieliczka , Bochnia , Cacica and Slanic Prahova ; and Ocnele Mari in the Southern Carpathians, but evaporites are also present in areas west of the Carpathians: Maramureș , eastern Slovakia (Solivar mine near Prešov ) and, to

507-645: The Talish Mountains , is mainly made up of Upper Cretaceous volcano-sedimentary deposits, with a strip of Paleozoic rocks and a band of Triassic and Jurassic rocks in the southern parts, both in a northwest–southeast direction. As the Tethys Sea was closed and the Arabian plate collided with the Iranian plate , and was pushed against it, and with the clockwise movement of the Eurasian plate towards

546-748: The Talysh ) runs south-southeastward almost along the western coast of the Caspian Sea. The Central Alborz (the Alborz Mountains in the strictest sense) runs from west to east along the entire southern coast of the Caspian Sea, while the Eastern Alborz Range runs in a northeasterly direction, toward the northern parts of the Khorasan region, southeast of the Caspian Sea. Mount Damavand , the highest mountain in Iran measuring 5,610.0 m (18,405.5 ft),

585-524: The supercontinent Pangaea broke up during the Triassic (200 million years ago). The name Paratethys was first used by Vladimir Laskarev in 1924. Laskarev's definition included only fossils and sedimentary strata from the sea of the Neogene system . This definition was later adjusted also to include the Oligocene series . The existence of a separate water body in these periods was deduced from

624-476: The Alborz Mountains. The extinct Caspian tiger also lived in the Alborz Mountains. Archaeological evidence from Alborz indicates that early human groups were present in the region since at least late Lower Paleolithic . The Darband Cave located at the Gilan Province contains evidence for late Lower Paleolithic . Stone artifacts and animal fossils were discovered by a group of archaeologists of

663-533: The Alborz, and continued with the uplift and folding of the older sedimentary rocks in the northwestern, central and eastern parts of the range, during the most important orogenic phases, which date from the Miocene and Pliocene epochs. While the southern slopes of the Alborz Mountains are usually semiarid or arid, with irregular and low precipitation, the northern slopes of the range are usually humid, especially in

702-549: The Central Alborz Range is formed mainly of Triassic and Jurassic rocks, while the northwestern section of the range is mainly composed of Jurassic rocks. Very thick beds of Tertiary (mostly Eocene ) green volcanic tuffs and lavas are found mainly in the southwestern and south-central parts of the range. The far northwestern part of the Alborz, that constitutes the Western Alborz Range or

741-494: The Eastern Alborz Range, the far eastern section is formed by Mesozoic (chiefly Triassic and Jurassic) rocks, while the western part of the Eastern Alborz Range is made primarily of Paleozoic rocks. Precambrian rocks can be found chiefly south of the city of Gorgan situated in the southeast of the Caspian Sea and, in much smaller amounts, in the central and western parts of the Central Alborz Range. The central part of

780-639: The Mediterranean fell dry during the Messinian salinity crisis (about 6 million years ago) there were phases when Paratethys water flowed into the deep Mediterranean basins. During the Pliocene epoch (5.33 to 2.58 million years ago) the former Paratethys was divided into a couple of inland seas that were at times completely separated from each other. An example was the Pannonian Sea ,

819-748: The Paratethys Sea. Paratethys formed about 34 Mya (million years ago) at the beginning of the Oligocene epoch, when the northern region of the Tethys Ocean (Peri-Tethys) was separated from the Mediterranean region of the Tethys realm due to the formation of the Alps , Carpathians , Dinarides , Taurus and Elburz mountains. During the Jurassic and Cretaceous periods, this part of Eurasia

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858-609: The Tortonian has been established in the Monte dei Corvi section near Ancona (Italy). The top of the Tortonian (the base of the Messinian ) is at the first appearance of the planktonic foram species Globorotalia conomiozea and is stratigraphically in the middle of magnetic chronozone C3Br.1r. In 2020, geologists reported two newly-identified supervolcano eruptions associated with the Yellowstone hotspot track, including

897-535: The bear bones, they probably accumulated through natural processes. During Middle Paleolithic period, Neanderthals were most probably were present in the region as their fossil have been found at northwest of Alborz, in the Azykh Cave . Their stone tools found in the Buzeir Cave and Kiaram cave and number of other surveyed sites. Evidence for Modern human comes from a river side site called Garm Roud in

936-521: The border of Azerbaijan along the western and entire southern coast of the Caspian Sea and finally runs northeast and merges into the smaller Aladagh Mountains and borders in the northeast on the parallel mountain ridge Kopet Dag in the northern parts of Khorasan . All these mountains are part of the much larger Alpide belt . The Alborz range is divided into the Western, Central, and Eastern Alborz Mountains. The Western Alborz Range (usually called

975-483: The feminine form of the adjective bṛzant- "high", the ancestor of modern Persian bouland and BarzBerazandeh , cognate with Sanskrit Brihat . Harā may be interpreted as "watch" or "guard", from an Indo-European root * ser- "protect". In Middle Persian, Harā Barazaitī became Harborz , Modern Persian Alborz , which is a cognate with Elbrus , the highest peak of the Caucasus . Zoroastrians seem to identify

1014-509: The fossil fauna, including mollusks, fish and ostracods . In periods in which the Paratethys or parts of it were separated from each other or from other oceans, a separate fauna developed which is found in sedimentary deposits. In this way, the paleogeographical development of the Paratethys can be studied. Laskerev's description of the Paratethys was anticipated much earlier by Sir Roderick Murchison in chapter 13 of his 1845 book. One of

1053-534: The geologic records from Paratethys particularly difficult to correlate with those from other oceans or seas because their faunas evolved separately at times. Stratigraphers of the Paratethys, therefore, have their own sets of stratigraphic stages which are still used as alternatives for the official geologic timescale of the ICS . The Paratethys spread over a large area in Central Europe and western Asia. In

1092-460: The key characteristics of the Paratethys realm, that is differentiating it from the Tethys Ocean , is the widespread development of endemic fauna, adapted to fresh and brackish waters like those that still exist in recent waters of the Caspian Sea. This distinctive fauna in which univalves of freshwater origin such as Limnex and Neritinex are associated with forms of Cardiacae and Mytili, common to partially saline or brackish waters, makes

1131-510: The megalake was home to many species found nowhere else, including molluscs and ostracods as well as miniature versions of whales, dolphins and seals. In 2023, Guinness World Records named this lake the largest in earth's history. Near the end of the Miocene, an event known as the Khersonian crisis, marked by rapidly fluctuating environmental factors and sea levels, wiped out much of the unique fish fauna of this megalake. When parts of

1170-672: The neighbouring Mediterranean region, probably via the Trans-Tethyan Corridor, an ancient sea-strait located in modern Slovenia . The open marine environments of Paratethys were short-lived, and halfway through the middle Miocene, progressive uplift of the central European mountain ranges and a eustatic drop isolated Paratethys from the global ocean triggering a salinity crisis in Central Paratethys. The " Badenian Salinity Crisis " spanned between 13.8 and 13.4 Mya. Thick evaporitic beds (salt and gypsum) formed in

1209-729: The range with the dwelling place of the Peshyotan , and the Zoroastrian Ilm-e-Kshnoom sect identifies Mount Damavand as the home of the Saheb-e-Dilan ('Masters of the Heart'). In his epic Shahnameh , the poet Ferdowsi speaks of the mountains "as though they lay in India ." This could reflect older usage, for numerous high peaks were given the name, and some even reflect it to this day, including Mount Elbrus in

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1248-513: The region's largest and most cataclysmic event – the Grey's Landing super-eruption – which had a volume of at least 2,800 cubic kilometres (670 cubic miles) and occurred around 8.72 Ma. Paratethys The Paratethys sea , Paratethys ocean , Paratethys realm or just Paratethys was a large shallow inland sea that stretched from the region north of the Alps over Central Europe to

1287-544: The same time the Alpine orogeny , a tectonic phase by which the Alps, Carpathians , Dinarides , Taurus , Elburz and many other mountain chains along the southern rim of Eurasia were formed. The combination of a drop in sea level and tectonic uplift resulted in the partial disconnection of the Tethys and Paratethys domains. Due to poor connectivity with the global ocean, the Paratethys realm became stratified and turned into

1326-638: The west it included in some stages the Molasse basin north of the Alps ; the Vienna Basin , the Outer Carpathian Basin , the Pannonian Basin , and further east to the basin of the current Black Sea and the Caspian Sea until the current position of the Aral Sea . The boundary between the Eocene and Oligocene epochs was characterized by a big drop of the global ( eustatic ) sea level and sudden steep cooling of global climates. At

1365-572: The western parts of the Central Alborz. The Alborz is the easternmost extent of many European plant species. In the southern slopes or the Elburz Range forest steppe ecoregion , the higher elevations are arid with few trees. Juniper is the most common tree in inaccessible areas and at high elevation, while common shrubs are pistachio , maple , and almond . But in the northern slopes, the Caspian Hyrcanian mixed forests ecoregion

1404-718: Was "shut down" during the middle Miocene, some 15 million years ago, when a widespread marine transgression , known as the Badenian Flooding, improved connections with the global ocean and triggered the ventilation of the deep waters of Paratethys. After the Badenian Flooding , in the middle Miocene , Paratethys was characterized by open-marine environments. Brackish and lacustrine basins turned into ventilated seas. Rich marine fauna containing sharks (e.g., megalodon ), corals , marine mammals , foraminifera and nanoplankton spread throughout Paratethys from

1443-660: Was at times reconnected with the Tethys or its successors (the Mediterranean Sea or the Indian Ocean ) during the Oligocene and the early and middle Miocene times, but at the onset of the late Miocene epoch, the tectonically trapped sea turned into a megalake from the eastern Alps to what is now Kazakhstan . From the Pliocene epoch onward (after 5 million years ago), Paratethys became progressively shallower. Today's Black Sea , Caspian Sea , Aral Sea , Lake Urmia , Namak Lake and others are remnants of

1482-688: Was covered by shallow seas that formed the northern margins of the Tethys Ocean. However, because Anatolia, the southern boundary of the Paleo-Tethys Ocean , is a part of the original continent of Cimmeria , the last remnant of the Paleo-Tethys might be oceanic crust under the Black Sea. The Tethys Ocean formed between Laurasia (Eurasia and North America) and Gondwana (Africa, India, Antarctica, Australia and South America) when

1521-588: Was introduced by Swiss stratigrapher Karl Mayer-Eymar in 1858. It was named after the Italian city of Tortona in the Piedmont region. The base of the Tortonian Stage is at the last common appearance of calcareous nanoplankton Discoaster kugleri and planktonic foram Globigerinoides subquadratus . It is also associated with the short normal polarized magnetic chronozone C5r.2n. A GSSP for

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