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61-642: Between 100 and 35 million years ago the area that is now the Eastern Desert was underwater, covered by the Tethys Ocean . During the Oligocene period, around 34 million years ago, the land began to tilt and the coastline was pushed back to the north and west. Concurrently, the basement complex to the east was uplifted, forming the mountain range of the Desert. In this same sequence of land movements,

122-426: A characteristic described in the common name. The leaves are thick, 5 to 8 cm (2.0 to 3.1 in) long, a bright, glossy green on the upper surface, and silvery-white, or grey, with very small matted hairs on the surface below. As with other Avicennia species, it has aerial roots (pneumatophores), which grow to a height of about 20 cm (7.9 in), and a diameter of 1 cm (0.4 in). These allow

183-537: A habitat for a variety of birdlife including the golden eagle and the bearded vulture , which are rarely found in any other areas of the Sahara. The Nile Valley is a central location for bird migration and there are more than 200 species of birds which pass through the western side of the Eastern desert during the migration seasons. The mining of precious metals dates back to Ancient Egyptian times and has carried on in

244-563: A large, fleshy seed, often germinating on the tree and falling as a seedling. The grey mangrove can experience stunted growth in water conditions that are too saline, but thrive to their full height in waters where both salt and fresh water are present. The species can tolerate high salinity by excreting salts through its leaves. The grey mangrove is a highly variable tree, with a number of ecotypes, and in forms closely resembling other species. It has been reported to tolerate extreme weather conditions, high winds, and various pests and diseases. It

305-430: A mix of grasses, succulents and herbaceous plants. Perennial vegetation is made up of succulents, grasses and woody shrub species. The vegetation cover on the coastal mountains is more dense than on the coastal desert. There are over 400 plant species within the coastal mountains eco-system, including shrubs, herbs and ferns. The distribution of these species varies subtly as the altitude changes. The plants which grow on

366-563: A rift which is now the Red Sea was opened up. The mountain range of the Eastern Desert runs between 80 and 137 kilometres (50 and 85 mi) inland from and parallel to the Red Sea Coast. It has peaks around 1,500 metres (4,900 ft) above sea level. The southern mountains are predominantly composed of igneous rock while the mountains to the north are composed of limestone . Separating the mountains are wide wadis which allow for

427-406: A saline environment. The salt marsh is created as mud builds up on tidal flats and plants grow on the mud, making it a more stable and permanent ecosystem. The two main types of vegetation in this area are mangrove and salt marsh vegetation. Avicennia marina , or grey mangrove is the dominant mangrove plant in the Red Sea area. It grows consistently along a large stretch of the Red Sea coast but

488-407: Is a pioneer in muddy soil conditions with a pH value of 6.5 to 8.0, but is intolerant of shade. A number of botanists have proposed division of the species, but currently three subspecies and one variety are recognised: It is distributed along Africa 's east coast, south-west , south and south-east Asia , Australia , and northern parts of New Zealand . It is one of the few mangroves found in

549-559: Is a species of mangrove tree classified in the plant family Acanthaceae (formerly in the Verbenaceae or Avicenniaceae ). As with other mangroves, it occurs in the intertidal zones of estuarine areas. Grey mangroves grow as a shrub or tree to a height of 3 to 10 m (10 to 33 ft), or up to 14 metres (46 ft) in tropical regions. The habit is a gnarled arrangement of multiple branches. It has smooth light-grey bark made up of thin, stiff, brittle flakes. This may be whitish,

610-671: Is a stand of grey mangroves in the Mandora Marsh , some 60 km (37 mi) from the coast. In South Australia along the Barker Inlet and Port River in Gulf St Vincent , as well as in sheltered bays in Spencer Gulf and the west coast of Eyre Peninsula , A. marina forests form hatcheries for much of the state's fish and shellfish commercial and recreational fisheries. In New Zealand, Avicennia marina

671-657: Is one of three species present in Africa's southernmost mangroves, in the estuary of South Africa 's Nahoon River at 32°56′S. The species is also found in Somalia . In Australia it occurs in every mainland state and extends much farther south than other mangroves, with its southern most limit at Corner Inlet (38°45′S) near Wilson's Promontory in Victoria . Its distribution is disjunct in Western Australia ;

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732-543: Is rarely seen to the North of the Egyptian city, Hurghada . Rhizophora mucronata , or loop-root mangrove, also grows co-dominantly with A.Marina in some areas along the coast but it is less prevalent. The loop-root mangrove is taller than the grey mangrove and thus, in areas where they do grow together, they form a two-tiered canopy of leaves. Small plants such as Cymodocea ciliata and Halophila oualis typically form

793-467: Is the easternmost part of the Eastern Desert, running between Eritrea and the Gulf of Suez. The distance between the coastline and the base of the mountain range varies between 30 and 175 kilometres (19 and 109 mi). The Eastern Desert has a semi-arid/arid/hyper-arid climate. On average, the region usually receives less than 25 millimetres (0.98 in) of rainfall per year in infrequent patterns. Most of

854-603: Is today. The vegetation growing in the Eastern Desert is classified as either ephemeral or perennial. Ephemeral vegetation are plants which usually have a single season lifespan due to their dependence on rain. Perennial plants live for two or more years. There are three main ecosystems within the coastal region of the Eastern Desert: littoral salt marsh , coastal desert and coastal mountains. The presence of sea spray, tidal movements and salt water seepage means that vegetation in these areas must be well adapted to living in

915-645: Is what is thought to have allowed for upwelling in the Arabian Sea and led to the establishment of the modern South Asian Monsoon . It also caused major modifications to the functioning of the AMOC and ACC . During the Oligocene (33.9 to 23 Mya), large parts of central and eastern Europe were covered by a northern branch of the Tethys Ocean, called the Paratethys . The Paratethys was separated from

976-513: The Paratethys when the Alpine front was still 100 km (62 mi) farther south. In 1885, the Austrian palaeontologist Melchior Neumayr deduced the existence of the Tethys Ocean from Mesozoic marine sediments and their distribution, calling his concept Zentrales Mittelmeer ( lit.   ' Central Mediterranean Sea ' ) and described it as a Jurassic seaway, which extended from

1037-768: The Rheic Ocean , which existed to the west of them in the Silurian Period. To the north of the Tethys, the then-land mass is called Angaraland and to the south of it, it is called Gondwanaland . From the Ediacaran (600  Mya ) into the Devonian (360 Mya ), the Proto-Tethys Ocean existed and was situated between Baltica and Laurentia to the north and Gondwana to the south. From

1098-828: The Silurian (440 Mya ) through the Jurassic periods, the Paleo-Tethys Ocean existed between the Hunic terranes and Gondwana. Over a period of 400 million years, continental terranes intermittently separated from Gondwana in the Southern Hemisphere to migrate northward to form Asia in the Northern Hemisphere. About 250 Mya, during the Triassic , a new ocean began forming in

1159-777: The Tethys Sea or the Neo-Tethys , was a prehistoric ocean during much of the Mesozoic Era and early-mid Cenozoic Era . It was the predecessor to the modern Indian Ocean , the Mediterranean Sea , and the Eurasian inland marine basins (primarily represented today by the Black Sea and Caspian Sea ). During the early Mesozoic, as Pangaea broke up, the Tethys Ocean was defined as the ocean located between

1220-490: The 1960s, "fixist" geologists, however, regarded Tethys as a composite trough, which evolved through a series of orogenic cycles. They used the terms 'Paleotethys', 'Mesotethys', and 'Neotethys' for the Caledonian , Variscan , and Alpine orogenies, respectively. In the 1970s and 1980s, these terms and 'Proto-Tethys', were used in different senses by various authors, but the concept of a single ocean wedging into Pangea from

1281-570: The Ancient Egyptians, and used during the Roman and Islamic periods. As well as precious materials, valuable building and sculpting materials have also been mined from the Eastern desert such as limestone, granite and marble. Today, most of the mining that occurs in and around the Eastern Desert is for crude oil and natural gas. The earliest signs of humans in the desert was found in the form of flint tools from 250,000 BC. Around 25,000 BC,

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1342-472: The Arabic word meaning fifty, as the storms occur on an average of fifty days per year. Carbon dating of samples of fossil tufas , a type of limestone which is deposited in the presence of high groundwater levels, has revealed that there have historically been two periods when the Eastern Desert was significantly wetter than it is today. These occurred in the late Pleistocene age, around 100,000 years ago, and

1403-873: The Aralo-Caspian Formation extending from close to the Danube delta across Crimea, up the east side of the Volga river to Samara, then south of the Urals to beyond the Aral Sea. Brackish and upper freshwater components (OSM) of the Miocene are now known to extend through the North Alpine foreland basin and onto the Swabian Jura with thickness of up to 250 m (820 ft); these were deposited in

1464-750: The Caribbean to the Himalayas. In 1893, the Austrian geologist Eduard Suess proposed the hypothesis that an ancient and extinct inland sea had once existed between Laurasia and the continents which formed Gondwana II. He named it the Tethys Sea after the Greek sea goddess Tethys. He provided evidence for his theory using fossil records from the Alps and Africa. He proposed the concept of Tethys in his four-volume work Das Antlitz der Erde ( The Face of

1525-477: The Earth ). In the following decades during the 20th century, " mobilist " geologists such as Uhlig (1911), Diener (1925), and Daque (1926) regarded Tethys as a large trough between two supercontinents which lasted from the late Palaeozoic until continental fragments derived from Gondwana obliterated it. After World War II , Tethys was described as a triangular ocean with a wide eastern end. From 1920s to

1586-454: The Eastern Desert until present day. From the early Pharaonic era (3000 BC), copper and gold were mined from the Desert and used to make tools and for jewellery and embellishment. It was not until much later, around 1000 BC, that iron was also discovered and began to be mined. Wadis were used as routes to cart the mined materials back to the civilisation. There were also mines for precious rocks such as emeralds and amethysts that were discovered by

1647-586: The Eurasian plate, which created new borders to the ocean, a land barrier to the flow of currents between the Indian and Mediterranean basins, and the orogenies of the Alpide belt (including the Alps , Himalayas , Zagros , and Caucasus Mountains ). All of these geological events, in addition to a drop in sea level rise from Antarctic glaciation, brought an end to the Tethys as it previously existed, fragmenting it into

1708-901: The Indian Ocean, the Mediterranean Sea, and the Paratethys . It was preceded by the Paleo-Tethys Ocean , which lasted between the Cambrian and the Early Triassic , while the Neotethys formed during the Late Triassic and lasted in some form up to the Oligocene – Miocene boundary (about 24–21 million years ago) when it completely closed. A portion known as the Paratethys was isolated during

1769-708: The Oligocene (34 million years ago) and lasted up to the Pliocene (about 5 million years ago), when it largely dried out. The modern inland seas of Europe and Western Asia, namely the Black Sea and Caspian Sea, are remnants of the Paratethys Sea. The sea is named after Tethys , who, in ancient Greek mythology, is a water goddess, a sister and consort of Oceanus , mother of the Oceanid sea nymphs and of

1830-550: The Paleo-Tethys formerly rested. During the Jurassic period about 150 Mya, Cimmeria finally collided with Laurasia and stalled, so the ocean floor behind it buckled under , forming the Tethys Trench . Water levels rose, and the western Tethys shallowly covered significant portions of Europe, forming the first Tethys Sea. Around the same time, Laurasia and Gondwana began drifting apart , opening an extension of

1891-636: The Tethys Sea between them which today is the part of the Atlantic Ocean between the Mediterranean and the Caribbean . As North and South America were still attached to the rest of Laurasia and Gondwana, respectively, the Tethys Ocean in its widest extension was part of a continuous oceanic belt running around the Earth between about latitude 30°N and the Equator . Thus, ocean currents at

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1952-601: The Tethys were eventually closed off in what is now the Middle East during the Miocene , as a consequence of the northern migration of Africa/Arabia and global sea levels falling due to the concurrent formation of the Antarctic Ice Sheet . This decoupling occurred in two steps, first around 20 Mya and another around 14 Mya. The complete closure of the Tethys led to a global reorganization of currents, and

2013-580: The Tethys with the Arctic Ocean . As theories have improved, scientists have extended the "Tethys" name to refer to three similar oceans that preceded it, separating the continental terranes: in Asia, the Paleo-Tethys (Devonian–Triassic), Meso-Tethys (late Early Permian –Late Cretaceous), and Ceno-Tethys (Late-Triassic–Cenozoic) are recognized. None of the Tethys oceans should be confused with

2074-469: The Tethys with the formation of the Alps, Carpathians , Dinarides , Taurus , and Elburz mountains during the Alpine orogeny . During the late Miocene , the Paratethys gradually disappeared, and became an isolated inland sea. Separation from the wider Tethys during the early Miocene initially led to a boost in primary productivity for the Paratethys, but this gave way to a total ecosystem collapse during

2135-480: The ancient continents of Gondwana and Laurasia . After the opening of the Indian and Atlantic oceans during the Cretaceous Period and the breakup of these continents over the same period, it came to be defined as the ocean bordered by the continents of Africa, Eurasia, India, and Australasia. During the early-mid Cenozoic, the Indian, African, Australian and Arabian plates moved north and collided with

2196-724: The arid regions of the coastal Arabian Peninsula , mainly in sabkha environments in the United Arab Emirates , Qatar , Bahrain , Oman , as well as in similar environments on both side of the Red Sea (in Yemen , Saudi Arabia , Egypt , Eritrea , and Sudan ), and Qatar and southern Iran along the Persian Gulf coast. It is a characteristic species of the Southern Africa mangroves ecoregion, and

2257-410: The desert through the wadis and then set up once they reached the port to embark on expeditions. The Ancient Egyptians exploited the desert resources of copper, gold, iron and precious stones. As well as for trade, they used these resources to improve their society and in their burials. Commercial trade increased further during the Roman period (30 BC–AD 395) and more trade routes were established across

2318-665: The desert. Red Sea ports were points of embarkation for trade with India. During the Ptolemaic and Roman period the chief port was Berenice Troglodytica , and the Via Hadriana led from Berenice to Antinoöpolis on the Nile. Items being traded diversified during this period to include goods such as fabrics and pearls. "Imperial Porphyry" was quarried at Mons Claudianus into the Byzantine era. The Romans set up multiple ports along

2379-423: The early Cenozoic, the Tethys Ocean could be divided into three sections: the Mediterranean Tethys (the direct predecessor to the Mediterranean Sea), the Peri-Tethys (a vast inland sea that covered much of eastern Europe and central Asia, and the direct predecessor to the Paratethys Sea), and the Indian Tethys (the direct predecessor to the Indian Ocean). The Turgai Strait extended out of the Peri-Tethys, connecting

2440-642: The east, roughly where Suess first proposed it, remained. In the 1960s, the theory of plate tectonics became established, and Suess's "sea" could clearly be seen to have been an ocean. Plate tectonics provided an explanation for the mechanism by which the former ocean disappeared: oceanic crust can subduct under continental crust . Tethys was considered an oceanic plate by Smith (1971); Dewey, Pitman, Ryan and Bonnin (1973); Laubscher and Bernoulli (1973); and Bijou-Duval, Dercourt and Pichon (1977). Avicennia marina See text . Avicennia marina , commonly known as grey mangrove or white mangrove ,

2501-411: The historic æra, a vast region of Europe and Asia was covered by a Mediterranean Sea of brackish water, of which the present Caspian is the diminished type. ... To render the distinction between these accumulations and all others clear and unambiguous, we have adopted the term Aralo-Caspian, first applied in a geographical sense, by our great precursor Humboldt, to this region of the globe. ... Judging from

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2562-487: The inland plateaus vary greatly in their distribution and species due to the difference in sandstone and limestone rock bases and the varying amount of rain and runoff water from the wadis. The wildlife of the Eastern Desert is quite different from that of the Western Desert, as the presence of the Nile River and the Red Sea Mountains provide variable eco-regions. Small mammals such as the fennec fox , golden spiny mouse , bushy-tailed jird , jerboa and other rodents live in

2623-547: The land underwent significant climatic change which transformed the grassy plains into desert. This made the land much less habitable and, as a result of this change, nomads which had inhabited the land that is now the Eastern Desert were driven towards the Nile River. Trade routes from the Nile to the Red sea were established through the Desert. Notably, there was a route between the Nile River and Mersa Gawasis , an Ancient Egyptian port. There were also many mines and quarries along this route. Boats were carried in pieces across

2684-412: The late Miocene as a result of rapid dissolution of carbonate . In Chapter 13 of his 1845 book, Roderick Murchison described a distinctive formation extending from the Black Sea to the Aral Sea in which the creatures differed from those of the purely marine period that preceded them. The Miocene deposits of Crimea and Taman (south of the Sea of Azov ) are identical with formations surrounding

2745-427: The littoral salt marsh and the base of the coastal mountains. In comparison to the littoral salt marsh area, the soil is non-saline and arid. The growing vegetation relies on the drainage of water from the mountains via wadis. As a result, growth of plants is seasonal, unlike in the littoral salt marsh. A greater variety of vegetation also grows in the area compared to the salt marsh area. The ephemeral vegetation includes

2806-406: The masses of water now separated from each other, from the Aral to the Black Sea inclusive, were formerly united in this vast pre-historical Mediterranean ; which (even if we restrict its limits to the boundaries we already know, and do not extend them eastward, amid low regions untrodden by geologists) must have exceeded in size the present Mediterranean! On the accompanying map, Murchison shows

2867-401: The mid Holocene age, around 6,000 years ago. The most recent wet period is known to have been a result of summer monsoonal rains that moved over the Desert from the Indian Ocean. During these times, some areas of the land were swamp. The mountains and desert plateaus were also able to sustain more vegetation and animals. In between these periods the desert climate has remained mostly arid, as it

2928-399: The mountains. In general, the northern sections of these plateaus have a limestone base while the southern sections are sandstone . The plateau between the Nile River and the mountains is also known as the inland Eastern Desert and is subdivided into four sections: The Cairo-Suez Desert, The Limestone Desert, The Sandstone (Idfu-Kom Ombo) Desert, and the Nubian Desert . The Red Sea coastland

2989-406: The on the plateaus of the Desert. Other larger mammals include the hyrax , Egyptian mongoose and the Egyptian wolf . The Red Sea Hills provide a unique mountainous habitat which increases the diversity of fauna in the Eastern Desert. Species found in the mountains include the aoudad , a mountain dwelling species of sheep, the Nubian ibex and the Dorcus gazelle. The mountain range also provides

3050-415: The plant to absorb oxygen, which is deficient in its habitat. These roots also anchor the plant during the frequent inundation of seawater in the soft substrate of tidal systems. The flowers range from white to a golden yellow colour, are less than 1 cm (0.4 in) across, and occur in clusters of three to five. The fruit contains large cotyledons that surround the new stem of a seedling. This produces

3111-436: The population of the Abrolhos Islands is 300 km (190 mi) further south than the nearest population of Shark Bay . Another mangrove system is found 500 km (310 mi) further south at Bunbury . This colonisation of southerly climes may have occurred relatively recently, perhaps several thousand years ago, when they were transferred by the Leeuwin Current . The most inland occurrence of mangroves in Australia

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3172-434: The present Caspian Sea , in which the univalves of freshwater origin are associated with forms of Cardiacae and Mytili that are common to partially saline or brackish waters. This distinctive fauna has been found throughout all the enormously developed Tertiary formations of the southern and south-eastern steppes. ... and leads at once to the conviction, that during long periods antecedent, as will be hereafter explained, to

3233-622: The rainfall occurs during the winter months around the mountains. The presence of the mountains can create a rain shadow for the rest of the Desert, contributing to the arid environment. Average temperatures are between 14 and 21 °C (57 and 70 °F) in winter (November–March) and 23.1 and 23.1 °C (73.6 and 73.6 °F) in summer (May–September). The weather is typically sunny; however, sandstorms can occur, usually between March and June. The storms ( khamsins ) are caused by tropical air moving up from Sudan, accompanied by strong winds and higher temperatures. The term khamsin comes from

3294-422: The recital of travellers and from specimens of the rock, we have no doubt that it extended to Khivah and the Aral Sea ; beyond which the low level of the adjacent eastern deserts would lead us to infer, that it spread over wide tracts in Asia now inhabited by the Turkomans and Kirghis , and was bounded only by the mountains of the Hindoo Kusk and Chinese Tartary . ... there can be no sort of doubt, that all

3355-423: The red sea coast to transport materials. Roman soldiers lived and worked at these ports. Their main sources of food were pigs, donkeys and camels. The Eastern Desert is a popular site for tours, safaris and other expeditions. Mining also still occurs in the Desert. Tethys Ocean The Tethys Ocean ( / ˈ t iː θ ɪ s , ˈ t ɛ -/ TEETH -iss, TETH - ; Greek : Τηθύς Tēthús ), also called

3416-589: The runoff of rainfall from the mountains to the Red Sea and the Nile River. The mountain range's highest peak is Gebel Shayeb EI-Banat at 2,184 metres (7,165 ft) above sea level. Other significant peaks include Jebel Erba (2,217 metres (7,274 ft)) Jabal Oda (2,160 metres (7,090 ft)), Jabal Shaib al Banat (2,087 metres (6,847 ft)), Jebel Hamata (1,961 metres (6,434 ft)), Gebel Amm Anad (1,782 metres (5,846 ft)), South Galala (1,464 metres (4,803 ft)), and North Galala (1,274 metres (4,180 ft)). Sedimentary plateaus run on either side of

3477-419: The southern end of the Paleo-Tethys Ocean. A rift formed along the northern continental shelf of Southern Pangaea (Gondwana). Over the next 60 million years, that piece of shelf, known as Cimmeria , traveled north, pushing the floor of the Paleo-Tethys Ocean under the eastern end of northern Pangaea (early / proto- Laurasia ). The Neo-Tethys Ocean formed between Cimmeria and Gondwana, directly over where

3538-422: The time around the Early Cretaceous ran very differently from the way they do today. Between the Jurassic and the Late Cretaceous , which started about 100 Mya, Gondwana began breaking up, pushing Africa and India north across the Tethys and opening up the Indian Ocean. Throughout the Cenozoic (66 million to the dawn of the Neogene, 23 Mya), the connections between the Atlantic and Indian Oceans across

3599-400: The undergrowth of the mangrove community. The salt marsh vegetation is made up of a mix of shrub, succulent and grass species. The growth of these plants often creates the coastal dunes as the root systems hold the sand in place when other areas are left exposed to wind erosion. Shrub communities Succulent communities Grass communities Coastal desert vegetation grown in the band between

3660-435: The world's great rivers, lakes and fountains. The eastern part of the Tethys Ocean is sometimes referred to as Eastern Tethys. The western part of the Tethys Ocean is called Tethys Sea, Western Tethys Ocean, or Paratethys or Alpine Tethys Ocean. The Black , Caspian , and Aral seas are thought to be its crustal remains, though the Black Sea may, in fact, be a remnant of the older Paleo-Tethys Ocean . The Western Tethys

3721-424: Was not simply a single open ocean. It covered many small plates, Cretaceous island arcs , and microcontinents . Many small oceanic basins ( Valais Ocean , Piemont-Liguria Ocean , Meliata Ocean ) were separated from each other by continental terranes on the Alboran , Iberian , and Apulian plates. The high sea level in the Mesozoic flooded most of these continental domains, forming shallow seas. During

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