Mount Roraima: Pacaraima Mountains (South America)

Mount Roraima: Pacaraima Mountains (South America)

Wed, 05/12/2021 - 19:56

Mount Roraima is the highest of the Pacaraima Mountains, a chain of tepui plateaus in South America. It serves as the tripoint of Venezuela, Guyana and Brazil. These tabletop mountains are considered to be the oldest geological formations on Earth.

Mount Roraima

Mount Roraima is the highest of the Pacaraima (or Pakaraima) Mountains, a chain of tepui plateaus (tabletop mountains) in South America. Reaching an elevation of 2,772 m (9,094 ft) asl, its summit area is bounded on all sides by cliffs and serves as the tripoint (triple border point) of Venezuela, Guyana and Brazil.

Mount Roraima lies on the Guiana Shield, in the southeastern corner of Venezuela's 30,000 sq km (12,000 sq mi) Canaima National Park, forming the highest peak of Guyana's Highland Range.

The highest point in Guyana and the highest point of the Brazilian state of Roraima lie on the plateau but Venezuela and Brazil have higher mountains elsewhere. The mountain's highest point is Laberintos del Norte.

Since long before the arrival of European explorers, the mountain has held a special significance for the indigenous people of the region and it is central to many of their myths and legends. In Brazil, the Monte Roraima National Park lies within the Raposa Serra do Sol Indigenous Territory.

Although the steep sides of the plateau make it difficult to access, it was the first recorded major tepui to be climbed: Sir Everard im Thurn walked up a forested ramp in December 1884 to scale the plateau. This is the same route hikers take today.

Many of the species found on Roraima are unique to the tepui plateaus with two local endemic plants found on the Roraima summit. Plants such as pitcher plants (Heliamphora), Campanula (a bellflower) and the rare Rapatea heather are commonly found on the escarpment and summit.

It rains almost every day of the year. Almost the entire surface of the summit is bare sandstone, with only a few bushes (Bonnetia roraimae) and algae present.

Low, scanty and bristling vegetation is also found in the small, sandy marshes that intersperse the rocky summit. Most of the nutrients that are present in the soil are washed away by torrents that cascade over the edge, forming some of the highest waterfalls in the world.

There are multiple examples of unique fauna atop Mount Roraima. Oreophrynella quelchii, commonly called the Roraima Bush Toad, is a diurnal toad usually found on open rock surfaces and shrubland. It is a species of toad in the family Bufonidae and breeds by direct development. The species is currently listed as vulnerable.

Pacaraima Mountains

The Pacaraima (or Pakaraima) Mountains are a mountain range located primarily in southwestern Guyana, extending into northern Brazil and eastern Venezuela. Monte Roraima National Park protects part of the range in Roraima, Brazil.

Extending for 400 km (250 mi) in an east–west direction, this chain of tepui plateaus (tabletop mountains) mark the borders between Brazil and southeastern Venezuela and between Brazil and west-central Guyana.

The Pacaraima Mountains are mostly forested, with a few savannas, especially at the base of Mount Roraima and on the Brazilian side of the range. The savannas host occasional Curatella americana trees below 2,000 m (6,500 ft). The highest elevations are situated within the Tepui ecoregion.

This central tabular upland of the Guiana Highlands form the drainage divide between the Orinoco Basin to the north and the Amazon Basin to the south. The rivers that rise on the plateau tops pour over the cliff edges in spectacular waterfalls such as Guyana's Kaieteur Falls.

These tabletop mountains are considered to be the oldest geological formations on Earth, dating back some two billion years to the Precambrian era.