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38-606: The Cotingo River has its headwaters at the foot of Mount Roraima in the Guayana Highlands region. The upper part of the Cotingo River basin is contained in the 116,748 hectares (288,490 acres) Monte Roraima National Park , a protected area created in 1989 that is fully contained in the Raposa Serra do Sol indigenous territory. The river runs for about 210 kilometres (130 mi) to its confluence with

76-519: A Royal Geographical Society-funded expedition to explore British Guiana (1835–1839). In 1840, the British government commissioned him to establish the boundaries between British Guiana and Venezuela. When he returned to the area in 1844 to study the local flora, he reported that the peak seemed inaccessible due to its towering cliffs. In 1864, German naturalist and botanist Carl Ferdinand Appun and British geologist Charles Barrington Brown arrived at

114-409: A large amount of quartz deposits, 98% are silica particles, forming white or pink crystals several centimeters long. These rocks sit on a granite and gneiss base and were originally covered by layers of Mesozoic clay, conglomerate, and diorite , but have been exposed by erosion and by orogeny over the past 180 million years, eroded by precipitation to form strange shapes. The soil of

152-491: A natural boulder. The base of the cliff is surrounded by steep slopes to the south and east, and the north and west sides form river valleys leading to the summit. The top of Mount Roraima has a length of more than 10 km (6.2 mi), a maximum width of 5 km (3.1 mi), an area of about 33–50 km (13–19 sq mi), an elevation of more than 2,200 m (7,200 ft), and an average elevation of 2,600–2,700 m (8,500–8,900 ft). The plateau

190-409: A result there is tension between the strong Indian population and the ranchers and settlers. Plans have been made for a hydro-electric project on the river. The first studies of the hydroelectric project were made in the 1970s. The proposed hydroelectric project would involve building five dams along the length of the river. In 2006 the federal senate approved a legislative decree aimed to authorise

228-472: Is a flat-topped mountain, typical of the Guyana Shield , with an elevation of about 1,200 m (3,900 ft) in the southeast and only about 600 m (2,000 ft) in the northwest. The south, southeast, east, northeast and northwest faces are all formed by straight cliffs up to about 1,000 m (3,300 ft) high. At the southern end of the mountain, part of the cliff has collapsed, forming

266-453: Is a pseudo- karst surface etched by heavy rainfall. The highest point is 2,810 m (9,219 ft) above sea level, located at the southern end of the plateau and the highest point in the state of Bolívar , 8.25 km (5.13 mi) north of the summit is another high point with an elevation of 2,772 m (9,100 ft), which is the highest point in Guyana. In the northern part of

304-440: Is chosen by almost all hikers, the only difficulty is that some streams and small waterfalls may become difficult to pass under heavy rain. However, the length of the trail requires climbers to spend one night at the base camp at the foot of the cliff at an elevation of about 2,000 meters, and another night at the summit, taking several days to explore the plateau and two days to descend. The best time to climb Mount Roraima

342-493: Is equally rich and 13,367 species of vascular plants have been found, approximately 40% of which is considered endemic. The shield is overlain by the largest expanse of tropical forest on any Precambrian shield area in the world. Guianan rain forest is similar in nature to Amazonian rain forest and known protected areas include the Iwokrama Forest of central Guyana, Kaieteur, Kanuku National Park of southern Guyana,

380-411: Is in the dry season, however, when the sun is very strong and the temperature is high, it can make the road to the mountain difficult. Guiana Shield The Guiana Shield ( French : Plateau des Guyanes, Bouclier guyanais ; Dutch : Hoogland van Guyana, Guianaschild ; Portuguese : Planalto das Guianas, Escudo das Guianas ; Spanish : Escudo guayanés ) is one of the three cratons of

418-680: Is the highest of the Pacaraima chain of tepuis (table-top mountain) or plateaux in South America . It is located at the junction of Brazil , Guyana and Venezuela . A characteristic large flat-topped mountain surrounded by cliffs 400–1,000 m (1,300–3,300 ft) high. The highest point of Mount Roraima is located on the southern edge of the cliff at an elevation of 2,810 m (9,220 ft) in Venezuela, and another protrusion at an elevation of 2,772 m (9,094 ft) at

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456-704: Is the highest summit of the larger Neblina massif , a highly eroded sandstone plateau that straddles the Venezuela-Brazil border and that has lost the typical tabletop shape of the other tepuis in the region. The Guiana Shield is one of the regions of highest biodiversity in the world, and has many endemic species. The region houses over 3000 vertebrate species: 1168 fresh water fish, 269 amphibians (54% endemics), 295 reptiles (29%), 1004 birds (7.7%), and 282 mammals (11%). Diversity of invertebrates remains largely undocumented, but there are several species of endemic butterflies and dung beetles. Plant life

494-462: The Orectanthe sceptrum , Sauvagesia imthurnii , Celiantha imthurniana , Roraima marsh pitchers ( Heliamphora nutans ), Gran Sabana sundew ( Drosera felix ), Roraima bladderworts ( Utricularia quelchii ), Roraima "azaleas" ( Bejaria imthurnii ) and many more. The fauna at the foot of the mountain are composed of a variety of mammals, and this huge diversity is particularly prominent in

532-830: The South American Plate . It is a 1.7 billion-year-old Precambrian geological formation in northeast South America that forms a portion of the northern coast. The higher elevations on the shield are called the Guiana Highlands , which is where the table-like mountains called tepuis are found. The Guiana Highlands are also the source of some of the world's most well-known waterfalls such as Angel Falls , Kaieteur Falls and Cuquenan Falls . The Guiana Shield underlies Guyana (previously British Guiana ), Suriname (previously Dutch Guiana ), and French Guiana (or Guyane ), much of southern Venezuela , as well as parts of Colombia and Brazil . The rocks of

570-658: The Surumu River , of which is the main tributary. It contains continuous stretches of rapids and waterfalls. The savanna region of the river basin has an equatorial climate with tropical monsoon rainfall. It is home to the Sun parakeet (Aratinga solstitialis), Rio Branco antbird (Cercomacra carbonaria), Finsch's euphonia (Euphonia finschi), Bearded tachuri (Polystictus pectoralis) and Hoary-throated spinetail (Synallaxis kollari). The river basin has high potential for mining, agriculture, ranching, and ecotourism , and as

608-479: The 19th century, when it was first climbed by a British expedition in 1884. Yet despite subsequent expeditions, its flora and geology remain largely unknown. The privileged setting and relatively easy access and climbing conditions on the south side of the cliffs make Mount Roraima a popular destination for hikers. Mount Roraima is located in the northern part of South America, the Pacarema Mountains in

646-540: The Amazon rainforest, such as sloths , anteaters , tapirs , armadillos , capybaras , opossums , agouti , weasels , raccoons , deer , cougars , and primates such as howler monkeys and capuchins . There are hundreds of species of birds, the most common of which include falcons , parrots , and owls . Some hummingbirds are endemic to the region. Due to low mobility relative to other species, reptiles and amphibians show large differences between individuals found at

684-468: The Guiana Shield consist of metasediments and metavolcanics ( greenstones ) overlain by sub-horizontal layers of sandstones , quartzites , shales and conglomerates intruded by sills of younger mafic intrusives such as gabbros . The oldest rocks in the shield consist of Archean Imataca Complex, composed of a quartz - feldspar gneiss and subordinate mafic gneiss. The Guri Fault marks

722-643: The Guiana Shield: The north-central part of the Guiana Highlands is dominated by high flat-topped peaks called tepuis , of the Roraima supergroup and Quasi-Roraima formation, and the rounded granite peaks of the Parguaza and Imataca complexes to the north and southwestern edges of the area. The highest point in the shield is Pico da Neblina in Brazil at 2,995 metres (9,826 ft). Pico da Neblina

760-538: The Royal Geographical Society that culminated on December 18, 1884, when the team met local people known as the Pemón who could have climbed to the top of Mount Roraima prior to their expedition. The explorers still believed the top of the cliff to be previously unknown to humans. Soon, many expeditions made up of botanists, zoologists and geologists made multiple expeditions to Mount Roraima to study

798-510: The Serra region. Wind power and solar power would be sufficient to meet the Raposa Serra do Sol's energy needs, but the project would be able to deliver power to the whole state. The indigenous people were concerned about the environmental impact and also the influx of non-indigenous people that would be expected. Mount Roraima Mount Roraima ( Spanish : Monte Roraima; Tepuy Roraima; Cerro Roraima ; Portuguese : Monte Roraima )

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836-860: The UNESCO World Heritage Site Central Suriname Nature Reserve of Suriname , the Guiana Amazonian Park in French Guiana and the Tumucumaque National Park in the Amapá State of Brazil . In Venezuela the forests are protected by Canaima , Parima-Tapirapeco and Serranía de la Neblina national parks. In 2014, the Government of Colombia designated a 250 hectare area of the Guiana Shield, as

874-446: The bottom and top of Mount Roraima. While species inhabiting forests at the foot of the plateau are common, such as green iguanas , pit vipers , coral snakes and pythons , those found at the top are even rarer. Cave fauna consists of many species of bats , grasshoppers , spiders and centipedes , but this fragile subterranean ecosystem is being disturbed by surface hikers, organic matter produced by tourists, and explorers over

912-560: The cliff at the foot of the mountain is an evergreen rainforest composed of trees 25–45 m (82–150 ft) high, and some can reach 60 m (200 ft). Vegetation is dominated by Arecaceae and Astragalus . The soils on the cliffs are more sandy, the climate is cooler, and the vegetation consists of bromeliads very similar to the Andes. The vegetation on the plateau is still largely unknown and consists mainly of bare rocks, forests of trees and epiphytes , and wet and dry savannas in

950-433: The crevices of the rock and flowed out in the form of waterfalls on the mountainside, creating many streams at the foot of the mountain. Due to the late exploration of this part of South America and the discovery of new species every year, the flora and fauna here are largely unknown. The currently identified species are strongly endemic, especially the fauna, which also puts them at a high risk of extinction. The bottom of

988-567: The eastern part of the Guyana Plateau, Brazil in the east accounting for 5% of its area, Guyana in the north accounting for 10%, and Venezuela in the south and west accounting for 85%. Access to Mount Roraima from the Venezuelan side is close to the road and relatively easy; however, for both Brazil and Guyana the area is completely isolated and can only be reached by a few days of forest hikes or small local airstrip. Mount Roraima

1026-512: The form of swamps. It is marked by numerous endemic species, especially carnivorous plants that capture insects, living in sandstone and leaching soils which lack the nitrates necessary for their development. There are fewer species in the vicinity of streams and ravines, and the trees are 8–15 m (26–49 ft) tall and have hard leaves that can adapt to harsh environmental conditions. The exposed rocks are occupied by lichens , algae and cyanobacteria . Endemic flora includes plants like

1064-525: The junction of the three countries in the north of the plateau is the highest point in Guyana. The name Mount Roraima came from the native Pemon people. Roroi in the Pemon language means "blue-green", and ma means "great". Leaching caused by intense rainfall has shaped the peculiar topography of the summit, and the geographical isolation of Mount Roraima has made it home to much endemic flora and fauna. Western exploration of Mount Roraima did not begin until

1102-589: The largest quartz cave in the world, discovered by the Oxford University Cave Club and the Venezuelan Speleological Society. These caves are formed by the infiltration of surface water, so the water level inside them depends largely on the precipitation on the surface of the plateau: prolonged drought can dry up waterways, and dry caves can also become underground rivers. The water that poured into it rushed into

1140-518: The mostly unknown flora and fauna and special geological conditions of the area. Mount Roraima and Mount Aoyan are the only flat-topped mountains in the Canaima National Park that can be climbed by hikers, with a monthly quota of 200 people. Its ascent takes three to five days in total, the summit route is on a natural slope on the southwestern cliffs of Mount Roraima, it does not require any special equipment or training, so it

1178-459: The plateau is the landmark of the border between Brazil, Venezuela and Guyana, with an elevation of 2,734 m (8,970 ft). Due to its height and proximity to the equator, Mount Roraima has a constant average annual temperature between 20–22 °C (68–72 °F) and annual rainfall of more than 1,500 mm (59 in), with 1,800–3,000 mm (71–120 in) in parts of the rainy season from April to November. The climatic conditions at

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1216-470: The sandstone matrix is highly acidic, poor in nutrients, and very fine. Intense rainfall prevents the fixation of nutrients and particles, thereby preventing the formation of hilltop vegetation and soil. The numerous caves and rifts in the interior of the plateau make Mount Roraima exhibit a pseudo- karst structure, and these caves form a network over 15 km (9.3 mi) long, with a total height difference of 73.21 m (240.2 ft). It contains

1254-461: The southeastern tip of Mount Roraima for observation and proposed to go up the mountain by hot air balloon. Although its vertical cliffs make access very difficult, Mount Roraima was the first large mesa to be climbed in the Guyana Plateau. Henry Whiteley , who studied the birds of the area, observed that the summit could be reached from the south with the help of ropes and ladders. Everard im Thurn and Harry Perkins led an expedition sponsored by

1292-533: The southern boundary of the complex. South of that fault are Early Proterozoic rocks consisting of the metavolcanic Pastora Supergroup and the granitic plutonic Supamo Complex. The Cuchivero Group consists of ash flow tuff and granitic plutonic rocks. The Early to Middle Proterozoic Roraima Group consists of continental clastic sedimentary rocks. These Precambrian sediments include quartz sandstones , quartzites , and conglomerates presumed to be 1.8 to 1.4 Ga in age. There are three upland areas of

1330-403: The top of the mountain differ significantly from its base, the high cloudiness in the region is associated with the prevailing northeasterly and southeasterly winds, and the relative humidity of the air remains between 75% and 85%. Mount Roraima is composed of Proterozoic age sandstone formed about 1.7 to 2 billion years ago, and hence amongst the oldest rocks on Earth. It contains

1368-712: The two subspecies of sparrow, the Zonotrichia capensis roraimae and the Zonotrichia capensis macconelli . One of the most well known endemic species is the Roraima toad ( Oreophrynella quelchii ). European discovery was in 1595, during a Spanish and British race to colonize this part of South America. The English poet, army officer and explorer Walter Raleigh described it as an immeasurable "crystal mountain" gushing countless waterfalls. The first expedition to Mount Roraima took place in 1838, when German scientist and explorer Robert Hermann Schomburgk observed it during

1406-669: The work, which would be undertaken in an indigenous area and would affect the Ingarikó, Makuxi, Patamona, Taurepang and Wapixana people. Nothing had been done by 2011 and the priority in Roraima state had turned to construction of the Bem Querer dam on the Branco River . The planned dam would have potential capacity of 136 MW and would flood an area of 37 square kilometres (14 sq mi). It would cost US$ 140 million. The first community to be flooded would be Tamanduá in

1444-465: The years. Pollutants such as fuel are washed into the ground by rainwater, which leads to the proliferation of microorganisms and causes ecological imbalance. Endemic species include rodents such as the Roraima climbing mouse ( Rhipidomys macconnelli roraimae ) or the rarer Roraima mouse ( Podoxymys roraimae ), as well as many birds such as the Greater flowerpiercer ( Diglossa major ) or

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