Pico 31 de Março, or Pico Trinta e Um de Março in full (), also known as Pico Phelps, is a

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher t ...

on the

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

–

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

border. At above sea level, it is Brazil's second highest mountain. It is part of the Neblina

massif A massif () is a principal mountain mass, such as a compact portion of a mountain range, containing one or more summits (e.g. France's Massif Central). In mountaineering literature, ''massif'' is frequently used to denote the main mass of an ...

, and the latter's summit

Pico da Neblina Pico da Neblina (, ''Mist Peak'') is the highest peak in Brazil, above sea level, in the Serra da Neblina, part of the Serra do Imeri, a section of the Guiana Highlands on the Brazil-Venezuela border. As determined by a border survey exped ...

, Brazil's highest summit, is only away. Pico 31 de Março can be considered a secondary summit of Pico da Neblina. Therefore, it is usually climbed by expeditions primarily aiming to reach the other peak. The two are linked by a

col A col is the lowest point on a mountain ridge between two peaks; a mountain pass or saddle. COL, CoL or col may also refer to: Computers * Caldera OpenLinux, a defunct Linux distribution * , an HTML element specifying a column * A collision sig ...

that can be easily traversed in a short trek of about an hour.

Discovery and naming

The peak was first discovered in 1954 by the Basset Maguire's expedition to the north side of the mountain massif. It was later climbed during the first attempt to climb Pico da Neblina, by a Brazilian army expedition. It received its name (meaning "March 31 Peak" in Portuguese) as a self-homage by the

military regime A military dictatorship, or a military regime, is a type of dictatorship in which power is held by one or more military officers. Military dictatorships are led by either a single military dictator, known as a strongman, or by a council of mi ...

instated in Brazil a few months earlier on that date, in a

coup d'état A coup d'état (; ; ), or simply a coup , is typically an illegal and overt attempt by a military organization or other government elites to unseat an incumbent leadership. A self-coup is said to take place when a leader, having come to powe ...

which was then officially called the " March 31 Revolution." The peak was finally reached in the following year by another army expedition to Pico da Neblina. The name was not changed after Brazil returned to democratic rule in 1985. The peak is known as Pico Phelps in Venezuela, and it is that country's highest point outside of the

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

Location

Pico da Neblina, in whose massif Pico 31 de Março is located, is the highest point on the

Guiana Shield The Guiana Shield (; ; ; ) is one of the three cratons of 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 ...

. ''Neblina'' means "fog" in both Portuguese and

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many countries in the Americas **Spanish cuisine **Spanish history **Spanish culture ...

. The mountains are contained in the Brazilian

Pico da Neblina National Park Pico da Neblina National Park () is a national park in the state of Amazonas in the north of Brazil, bordering on Venezuela. It overlaps with several indigenous territories, which creates tensions over land use, as does the military presence due ...

; their northern slopes are also protected in Venezuela's Serranía de la Neblina National Park. The twin parks, together with the neighbouring

Parima Tapirapecó National Park Parima Tapirapecó National Park (''Parque Nacional Parima Tapirapecó'') is a Venezuelan national park in the southern state of Amazonas. Location The Parima Tapirapecó National Park is in the Atabapo and Río Negro municipalities. It is ...

(Venezuela), form a protected area complex of about 80,000 km², possibly the largest national park system on tropical rainforests in the world.

Elevation measurements

For 39 years, based on a never before contested measurement performed in 1965 by

topographer Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the landforms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary scienc ...

José Ambrósio de Miranda Pombo, using a

theodolite A theodolite () is a precision optical instrument for measuring angles between designated visible points in the horizontal and vertical planes. The traditional use has been for land surveying, but it is also used extensively for building and ...

, the elevation of Pico 31 de Março was thought to be , but a much more accurate measurement performed in 2004 with state-of-the-art

GPS The Global Positioning System (GPS) is a satellite-based hyperbolic navigation system owned by the United States Space Force and operated by Mission Delta 31. It is one of the global navigation satellite systems (GNSS) that provide geol ...

equipment by

cartographer Cartography (; from , 'papyrus, sheet of paper, map'; and , 'write') is the study and practice of making and using maps. Combining science, aesthetics and technique, cartography builds on the premise that reality (or an imagined reality) can ...

Marco Aurélio de Almeida Lima, member of a Brazilian army expedition, put it at . This was then officially recognised by the

Brazilian Institute of Geography and Statistics The Brazilian Institute of Geography and Statistics (; IBGE) is the agency responsible for official collection of statistical, geographic, cartographic, geodetic and environmental information in Brazil. IBGE performs a decennial national cen ...

(IBGE), the federal government's official geographic survey and census agency, which jointly organised the expeditio

In February 2016, IBGE slightly revised again the official altitude of Pico 31 de Março to , a 1.52-metre difference. There was no new expedition or field measurement at the time; the new value is simply a mathematical recalculation of the altitude, based on the previously obtained GPS field data, taking into account a newly available, more precise mapping of the Brazilian territory regarding the

geoid The geoid ( ) is the shape that the ocean surface would take under the influence of the gravity of Earth, including gravitational attraction and Earth's rotation, if other influences such as winds and tides were absent. This surface is exte ...

(the imaginary surface based on the

Earth Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

gravitational field In physics, a gravitational field or gravitational acceleration field is a vector field used to explain the influences that a body extends into the space around itself. A gravitational field is used to explain gravitational phenomena, such as ...

that is the reference for altitudes). This explains why Pico da Neblina and Pico 31 de Março, which are next to each other, had both exactly the same altitude correction.

Geology and topography

The Neblina massif is a

glaciated A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires d ...

tor Tor, TOR or ToR may refer to: Places * Toronto, Canada ** Toronto Raptors * Tor, Pallars, a village in Spain * Tor, former name of Sloviansk, Ukraine, a city * Mount Tor, Tasmania, Australia, an extinct volcano * Tor Bay, Devon, England * Tor ...

composed of a tilted block of

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

overlying

Precambrian The Precambrian ( ; or pre-Cambrian, sometimes abbreviated pC, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of t ...

metamorphic rock Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock ( protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, caus ...

s. In contrast to the sharp tooth shape of its higher neighbour, Pico 31 de Março has a smoother shape and is sometimes difficult to be clearly distinguished from Pico da Neblina on photographs, depending on the angle and distance from which the photograph was taken. Due to its equatorial latitude, while it can be cold on top, sub-freezing temperatures and frost appear to be rare (no permanent measurements are undertaken), and there is no snow. One non-authoritative source gives an average temperature of during the day and at night for nearby Pico da Neblina.

Access

Due to its location in a national park in a border area that is also part of

Yanomami The Yanomami, also spelled Yąnomamö or Yanomama, are a group of approximately 35,000 indigenous people of the Americas, indigenous people who live in some 200–250 villages in the Amazon rainforest on the border between Venezuela and Brazil. ...

territory, access to the area is restricted and depends on a special permit by the

Chico Mendes Institute for Biodiversity Conservation The Chico Mendes Institute for Biodiversity Conservation ( Portuguese: ''Instituto Chico Mendes de Conservação da Biodiversidade'', ICMBio) is a government agency under the administration of the Brazilian Ministry of the Environment. It is nam ...

(ICMBio). The permit can be obtained at ICMBio's office in

São Gabriel da Cachoeira São Gabriel da Cachoeira (Portuguese language, Portuguese: ''Saint Gabriel of the Waterfall'') is a Municipalities of Brazil, municipality located on the northern shore of the Rio Negro (Amazon), Rio Negro River, in the region of Cabeça do Ca ...

, but all climbers must take an accredited local guide. A four-day trek each way should be expected, three of which consisting of a jungle trek in the rainforest that can be as hard and challenging as the climb itself. Rescue is close to impossible in the area.

Onchocerciasis Onchocerciasis, also known as river blindness, is a disease caused by infection with the parasitic worm ''Onchocerca volvulus''. Symptoms include severe itching, bumps under the skin, and blindness. It is the second-most common cause of blindne ...

or "river blindness," a

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The ent ...

disease that can cause permanent

blindness Visual or vision impairment (VI or VIP) is the partial or total inability of visual perception. In the absence of treatment such as corrective eyewear, assistive devices, and medical treatment, visual impairment may cause the individual difficul ...

and is transmitted by a

black fly A black fly or blackfly (sometimes called a buffalo gnat, turkey gnat, or white socks) is any member of the family Simuliidae of the Culicomorpha infraorder. It is related to the Ceratopogonidae, Chironomidae, and Thaumaleidae. Over 2,200 s ...

, is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

in the area, albeit with a low incidence;

malaria Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...

and yellow fever transmission are also possible. Therefore, climbers are advised not only to take the utmost precaution in avoiding insect bites, but also to discuss preventive and/or therapeutic strategies with their physicians.

References

* Maguire, Bassett and Reynolds, Charles D. (1955) "Cerro de la Neblina, Amazonas, Venezuela: A Newly discovered Sandstone Mountain" ''Geographical Review'' 45(1): pp. 27–51 * Instituto Brasileiro de Desenvolvimento Florestal (1979) ''Plano do Sistema de Unidades de Conservação do Brasil''. Ministério da Agricultura (MA), Instituto Brasileiro de Desenvolvimento Florestal (IBDF) and Fundação Brasileira para a Conservação da Natureza (FBCN), Brasília, D.F.
OCLC 6944034
In Portuguese, covers the geology, geomorphology, climate, soils, vegetation and fauna of Pico da Neblina National Park. * Gentry, A.H. (1986) "Exploring the Mountain of the Mists" ''Science Year: The World Book Science Annual'' pp. 124–139

External links

Best article of the 31 de March Peak, with the full article detailing the expedition, maps, tracklogs, camps, logistics and many photos (clubedosaventureiros.com)

Picasa gallery of photographs
from two Brazilian private expeditions to Pico da Neblina, maintained by Orlei S. Jr. of the Brazilia
Mundo Vertical
mountaineering site, where some pictures also show Pico 31 de Março as a rounded secondary peak. There is also a picture of Pico da Neblina taken from the top of 31 de Março, showing how close the two peaks are.
"Pico 31 de Março" Peakbagger
{{DEFAULTSORT:Pico 31 de Marco 31 de Marco 31 de Marco Brazil–Venezuela border International mountains of South America Landforms of Amazonas (Brazilian state)