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Mount Roraima

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Mount Roraima (Spanish: Monte Roraima; Tepuy Roraima; Cerro Roraima; Portuguese: Monte Roraima) is the highest of the Pacaraima chain of tepuis (table-top mountain) or plateaux in South America.[4]: 156 [c] 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,[d] and another protrusion at an elevation of 2,772 m (9,094 ft) at 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".[5]

Mount Roraima
Mount Roraima as seen from the Venezuelan side
Highest point
Elevation2,810 m (9,220 ft)[1]
Prominence2,338 m (7,671 ft)[1]
Listing
Coordinates5°08′36″N 60°45′45″W / 5.14333°N 60.76250°W / 5.14333; -60.76250
Geography
Mount Roraima is located in South America
Mount Roraima
Mount Roraima
Location in South America
Mount Roraima is located in Brazil
Mount Roraima
Mount Roraima
Mount Roraima (Brazil)
Mount Roraima is located in Guyana
Mount Roraima
Mount Roraima
Mount Roraima (Guyana)
Mount Roraima is located in Venezuela
Mount Roraima
Mount Roraima
Mount Roraima (Venezuela)
LocationBorder region between Brazil (Roraima), Guyana (Cuyuni-Mazaruni) and Venezuela (Bolívar)
Countries
Parent rangePacaraima Mountains, Guayana Highlands
Geology
Mountain typePlateau
Climbing
First ascent1884, led by Sir Everard im Thurn and accompanied by Harry Inniss Perkins and several natives[2][3]: 497 [a][b]
Easiest routeHiking path

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 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.[6]

Geography

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Mount Roraima is located in the northern part of South America, the Pacarema Mountains in 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%.[7][8] 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.[9][10][11]

Mount Roraima is a flat-topped mountain, typical of the Guyana Shield,[12] 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.[7] 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 a natural boulder.[7][13][12][14] 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.[10][13]

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 km2 (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).[7][15][16] The plateau is a pseudo-karst surface etched by heavy rainfall.[13] 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,[7][9][16] 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.[17] In the northern part of the plateau is the landmark of the border between Brazil, Venezuela and Guyana, with an elevation of 2,734 m (8,970 ft).[18]

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.[19] The climatic conditions at 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%.[9][15][20]

Geology

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Mount Roraima is composed of Proterozoic age sandstone formed about 1.7 to 2 billion years ago,[11][14][15][21] and hence amongst the oldest rocks on Earth. It contains a large amount of quartz deposits,[9][14][15][21] 98% are silica particles,[16] forming white or pink crystals several centimeters long.[14][15] 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.[9][12] The soil of the sandstone matrix is highly acidic, poor in nutrients, and very fine.[12] Intense rainfall prevents the fixation of nutrients and particles, thereby preventing the formation of hilltop vegetation and soil.[9][21]

The numerous caves and rifts in the interior of the plateau make Mount Roraima exhibit a pseudo-karst structure,[9][22] 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).[23] It contains the largest quartz cave in the world, discovered by the Oxford University Cave Club and the Venezuelan Speleological Society.[24][22] 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.[16] The water that poured into it rushed into 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.[14]

Ecology

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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.[9] The currently identified species are strongly endemic, especially the fauna, which also puts them at a high risk of extinction.[12] The bottom of 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).[12] Vegetation is dominated by Arecaceae and Astragalus.[9] The soils on the cliffs are more sandy, the climate is cooler, and the vegetation consists of bromeliads very similar to the Andes.[9] 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 the form of swamps.[9] 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.[21][14][12] 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.[9] The exposed rocks are occupied by lichens, algae and cyanobacteria.[16]

Endemic flora includes plants like the Orectanthe sceptrum,[25] Sauvagesia imthurnii,[26] Celiantha imthurniana,[27] Roraima marsh pitchers (Heliamphora nutans), Gran Sabana sundew (Drosera felix),[28] Roraima bladderworts (Utricularia quelchii), Roraima "azaleas" (Bejaria imthurnii)[29] and many more.[30]

The fauna at the foot of the mountain are composed of a variety of mammals, and this huge diversity is particularly prominent in 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.[9] Due to low mobility relative to other species, reptiles and amphibians show large differences between individuals found at the bottom and top of Mount Roraima.[9] 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.[8] Cave fauna consists of many species of bats, grasshoppers, spiders and centipedes,[9][22][16] but this fragile subterranean ecosystem is being disturbed by surface hikers, organic matter produced by tourists, and explorers over the years. Pollutants such as fuel are washed into the ground by rainwater, which leads to the proliferation of microorganisms and causes ecological imbalance.[22]

Endemic species include rodents such as the Roraima climbing mouse (Rhipidomys macconnelli roraimae)[31][32] or the rarer Roraima mouse (Podoxymys roraimae),[30] as well as many birds such as the Greater flowerpiercer (Diglossa major) or the two subspecies of sparrow, the Zonotrichia capensis roraimae[33][30] and the Zonotrichia capensis macconelli.[30][33] One of the most well known endemic species is the Roraima toad (Oreophrynella quelchii).[30]

Exploration

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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.[15][8] The first expedition to Mount Roraima took place in 1838, when German scientist and explorer Robert Hermann Schomburgk observed it during 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.[14][8] In 1864, German naturalist and botanist Carl Ferdinand Appun and British geologist Charles Barrington Brown arrived at the southeastern tip of Mount Roraima for observation and proposed to go up the mountain by hot air balloon.[8]

Although its vertical cliffs make access very difficult, Mount Roraima was the first large mesa to be climbed in the Guyana Plateau.[9][21] 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.[8] Everard im Thurn and Harry Perkins led an expedition sponsored by 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.[14] Soon, many expeditions made up of botanists, zoologists and geologists made multiple expeditions to Mount Roraima to study the mostly unknown flora and fauna and special geological conditions of the area.[21][22]

Climbing

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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.[9][16] Its ascent takes three to five days in total,[7][14] the summit route is on a natural slope on the southwestern cliffs of Mount Roraima,[13][15][21] it does not require any special equipment or training, so it is chosen by almost all hikers,[15][21] the only difficulty is that some streams and small waterfalls may become difficult to pass under heavy rain.[14][21] 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.[14][15] The best time to climb Mount Roraima 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.[15][21]

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  •  
    The cliffs of Mount Roraima
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    Tripoint marker where the borders of Brazil, Guyana, and Venezuela meet on top of Mount Roraima
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    The Roraima Falls
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    Mount Roraima and the falls as seen from the Venezuela side
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    Roraima, A Remarkable Range of Sandstone Mountains in Guiana. Painters Charles Bentley and Robert H. Schomburgk, engraver George Barnard. Published by Ackermann, 1840
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    An illustration of Mount Roraima in Canoe and Camp Life in British Guiana, 1876

Notes

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  1. ^ For all around wore rocks and pinnacles of rocks of seemingly impossibly fantastic forms, standing in apparently impossibly fantastic ways — nay, placed one on or next to the other in positions seeming to defy every law of gravity — rocks in groups, rocks standing singly, rocks in terraces, rocks as columns, rocks as walls and rocks as pyramids, rocks ridiculous at every point with countless apparent caricatures of the faces and forms of men and animals, apparent caricatures of umbrellas, tortoises, churches, cannons, and of innumerable other most incongruous and unexpected objects.[3]
  2. ^ Lord Aberdare said that Mr. Perkins, who accompanied Mr. im Thurn in the ascent of the mountain, had fared little better, inasmuch as he also had been severely attacked by fever since his return, and though present that evening, was still too weak to read his notes.[2]
  3. ^ "Mount Roraima is the point where the boundaries of Venezuela, Brazil and British Guiana actually meet, and a stone stands on its summit, placed there by the International Commission in 1931." — Michael Swan (1957)[4]
  4. ^ Maverick Rock, a rock formation on the plateau.

References

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  1. ^ a b "Monte Roraima, Venezuela". Peakbagger.com.
  2. ^ a b "Mr. im Thurn's Achievement" (PDF). The New York Times. New York, NY. May 22, 1885. p. 3. ISSN 0362-4331. OCLC 1645522. Retrieved November 15, 2009.
  3. ^ a b im Thurn, Everard (August 1885). "The ascent of Mount Roraima" (PDF). Proceedings of the Royal Geographical Society and Monthly Record of Geography. New Monthly Series. 7 (8). London, U.K.: Blackwell Publishing, on behalf of the Royal Geographical Society, with the Institute of British Geographers: 497–521. doi:10.2307/1800077. ISSN 0266-626X. JSTOR 1800077. OCLC 51205375. Retrieved November 14, 2009 – via Google Books.
  4. ^ a b Swan, Michael (1957). British Guiana. London, U.K.: Her Majesty's Stationery Office. OCLC 253238145.
  5. ^ "The meaning behind the name 'Mount Roraima'". Explorationjunkie.com. 7 December 2019. Retrieved 7 December 2019.
  6. ^ "Mount Roraima". Encyclopædia Britannica. Retrieved 2012-02-06.
  7. ^ a b c d e f "Monte Roraima, Venezuela". Peakbagger.com. Archived from the original on 2017-09-19. Retrieved 2012-04-24.
  8. ^ a b c d e f "Roraima Tepuy". lagransabana.com. La Gran Sabana y Canaima. Archived from the original on 2012-04-23. Retrieved 2022-03-21.
  9. ^ a b c d e f g h i j k l m n o p q Canaima National Park Venezuela. Programme des Nations unies pour l'environnement. 2011. p. 8. Archived from the original on 2013-12-06. Retrieved 2022-03-21.
  10. ^ a b Caraurín, Venezuela; Brazil; Guyana. U.S. National Imagery and Mapping Agency. November 1994. Archived from the original on 2016-03-03. Retrieved 2022-03-21 – via lib.utexas.edu.
  11. ^ a b MacDonald, Dougald. "New route in remote Guyana". Climbing.com. Archived from the original on 2012-01-19. Retrieved 2012-04-24.
  12. ^ a b c d e f g "Ambiente Natural". inparques.gob.ve. Venezuela: Instituto Nacional de Parques. Archived from the original on 2020-06-17. Retrieved 2012-04-24.
  13. ^ a b c d "Карта Рораймы, Венесуэла". geopoesia.ru (in Russian). 1952. Archived from the original on 2014-01-17. Retrieved 2012-04-24.
  14. ^ a b c d e f g h i j k Elms, Lindsay. "Mount Roraima: An Island Forgotten by Time". Archived from the original on 2007-05-09. Retrieved 2022-03-21 – via shaw.ca.
  15. ^ a b c d e f g h i j Dana Kennedy (2012-04-12). "An unearthly plateau in Venezuela". The Seoul Times. Archived from the original on 2022-01-09. Retrieved 2022-03-21.
  16. ^ a b c d e f g Šmída, Braňislav; Audy, Marek; Vlček, Lukáš. The speleological expedition Roraima 2003 Cueva Ojos de Cristal. p. 20. Archived from the original on 2022-01-09. Retrieved 2022-03-21.
  17. ^ "Mount Roraima-Guyana high point, Guyana / Venezuela". Peakbagger.com. Retrieved 2012-04-11.
  18. ^ "Monte Roraima – triple-country Point, Brazil / Guyana / Venezuela". Peakbagger.com. Retrieved 2012-04-11.
  19. ^ "Información General". inparques.gob.ve. Venezuela: Instituto Nacional de Parques. Retrieved 2012-04-24.
  20. ^ "Santa Elena de Uairen, Venezuela: Climate, Global Warming, and Daylight Charts and Data". climate-charts.com. World Climate. Archived from the original on 2011-09-25. Retrieved 2012-04-24.
  21. ^ a b c d e f g h i j "Monte Roraima". Summitpost. 2012-04-12. Archived from the original on 2022-02-08. Retrieved 2022-03-21.
  22. ^ a b c d e "Notas sobre la exploración del sistema kárstico de Roraima Sur, Estado Bolívar". Boletín de la Sociedad Venezolana de Espeleología (in Spanish): 8. 2004. ISSN 0583-7731. Archived from the original on 2014-01-17. Retrieved 2022-03-21.
  23. ^ Gulden, Bob (2013-07-31). "World's longest caves". cavebob.com. Archived from the original on 2021-05-09. Retrieved 2022-03-21.{{cite web}}: CS1 maint: unfit URL (link)
  24. ^ Crosby, Pip. "OUCC-SVE Roraima expedition". oucc.org.uk. Retrieved 2024-04-29.
  25. ^ "Orectanthe sceptrum", Wikipedia (in German), 2017-11-11, retrieved 2024-08-01
  26. ^ "Sauvagesia imthurniana". iNaturalist United Kingdom. Retrieved 2024-08-01.
  27. ^ "Celiantha imthurniana (Oliv.) Maguire | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2024-08-01.
  28. ^ "Killerpflanzen - Killerpflanzen - Drosera felix". www.killerpflanzen.com. Retrieved 2024-08-01.
  29. ^ "Bejaria imthurnii description". www.nybg.org. Retrieved 2024-08-01.
  30. ^ a b c d e "Homepage of Vladimir Dinets - Mount Roraima, Part 7". dinets.info. Retrieved 2024-08-01.
  31. ^ Wilson, Don E.; Reeder, DeeAnn (2005-12-31). "Rhipidomys macconnelli De Winton 1900". doi:10.5281/zenodo.11325694. {{cite journal}}: Cite journal requires |journal= (help)
  32. ^ Campos, Bruno Augusto Torres Parahyba; Percequillo, Alexandre Reis; Miranda, Gustavo; Langguth, Alfredo (2022-05-31). "Two new species of Rhipidomys (Rodentia: Sigmodontinae) from Eastern Brazil, with comments on the taxonomy of the genus". Hystrix, the Italian Journal of Mammalogy. 33 (2): 139–157. doi:10.4404/hystrix-00443-2021. ISSN 0394-1914.
  33. ^ a b "Zonotrichia capensis (Rufous-collared Sparrow) - Avibase". avibase.bsc-eoc.org. Retrieved 2024-08-01.

Further reading

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  • Aubrecht, R.; Lánczos, T.; Gregor, M.; Schlögl, J.; Šmída, B.; Liščák, P.; et al. (15 September 2011). "Sandstone caves on Venezuelan tepuis: Return to pseudokarst?". Geomorphology. 132 (3–4): 351–365. doi:10.1016/j.geomorph.2011.05.023.
  • Aubrecht, R.; Lánczos, T.; Gregor, M.; Schlögl, J.; Šmída, B.; Liščák, P.; et al. (2013) [30 November 2012 (online)]. "Reply to the comment on "Sandstone caves on Venezuelan tepuis: Return to pseudokarst?"". Geomorphology. doi:10.1016/j.geomorph.2012.11.017.
  • MacCulloch, R.D.; Lathrop, A.; Reynolds, R.P.; Senaris, J.C.; Schneider, G.E. (2007). "Herpetofauna of Mount Roraima, Guiana Shield region, northeastern South America". Herpetological Review. 38: 24–30.
  • Sauro, F.; Piccini, L.; Mecchia, M.; de Waele, J. (2013) [29 November 2012 (online)]. "Comment on "Sandstone caves on Venezuelan tepuis: Return to pseudokarst?" by R. Aubrecht, T. Lánczos, M. Gregor, J. Schlögl, B. Smída, P. Liscák, Ch. Brewer-Carías, L. Vlcek (2011)". Geomorphology. 132: 351–365. doi:10.1016/j.geomorph.2012.11.015.
  • Warren, A. (1973). Roraima: Report of the 1970 British expedition to Mount Roraima in Guyana, South America. Oxford UK: Seacourt Press.
  • Zahl, Paul A. (1940). To the Lost World. London, UK: George G. Harrap & Co.
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