Beez Neez now Chy Whella

Tepuy

Big Bear and Pepe Millard

Sat 10 Oct 2009 22:30

Tepuy or Tepui

Sir Walter Raleigh described what was possibly a tepuy (table top mountain), and he is sometimes said to have discovered Angel Falls, but these claims are considered "far-fetched". They were spotted in 1912 by the Venezuelan explorer Ernesto Sanchez La Cruz, but he did not publicise his discovery. They were not known to the outside world until American aviator Jimmie Angel flew over them on the 16^th of November 1933 on a flight while he was searching for a valuable ore bed.

Returning on the 9^th of October 1937, Angel tried to land his Flamingo monoplane "El Rio Caroni" atop Auyan-tepui, but the plane was damaged when the wheels sunk into the marshy ground, and he and his three companions, including his wife Marie, were forced to descend the tepui on foot. It took them 11 days to make their way back to civilization, but news of their adventure spread, and the waterfall was named "Angel Falls" in his honour.

The most famous tepuis in the park are Mount Roraima, the tallest and easiest to climb, and Auyantepui, from which fall the Angel Falls, the highest waterfall in the world. The tepuis are sandstone and date back to a time when South America and Africa were part of a super-continent.

The park is home to indigenous Pemon Indians, part of the Carib linguistic group. The Pemon have an intimate relationship with the tepuis, and believe they are the home of the 'mawari' spirits. The park is relatively remote, with only a few roads connecting towns. Most transport within the park is done by light plane from the airstrips built by various Capuchin missions, or by foot and canoe.

The main inhabitants are the Pemons, they have developed some basic and luxurious hotel locations which is mainly visited by European tourists.

The plateau of Mount Roraima. The peculiar rock formation is caused by erosion.

These table-top mountains are the remains of a large, sandstone plateau that once covered the granite basement complex between the north border of the Amazon Basin and the Orinoco, between the Atlantic coast and the Rio Negro. Throughout the course of the history of Earth, the plateau was eroded, and the tepuis were formed from the remaining monadnocks. There are one hundred and fifteen such mesas in the Gran Sabana in the south-east of Venezuela on the border with Guyana and Brazil, where the highest concentration of tepuis is found. The precipitous mountains tower over the surrounding area by up to 1,000 metres. On the top of the mountains grow various types of forests with a wide variety of orchids and bromeliad species. Because of their great age, some tepuis exhibit surface features and subsurface caves that are typical of more water-soluble rock such as limestone. Caves here include the six hundred and seventy one metre deep Abismo Guy Collet, the deepest quartzite cave in the world. Some of the mesas are pocked with giant sinkholes up to three hundred metres in diameter and with sheer walls up to three hundred metres deep. These sinkholes are formed when the roofs of tunnels carved by underground rivers collapse. Ptari Tepui's sheer rock walls are so isolated, it is believed a high number of endemic plant and animal species could be found there. Sarisarinama Tepui, famous for its almost perfectly circular sinkholes which go straight down from the mountain top - the largest such sinkhole is three hundred and fifty metres in diameter and depth (purportedly created by groundwater erosion). They harbour an ecosystem composed of unique plant and animal species at the bottom.

Flora and fauna

The plateau of the mesas is completely isolated from the ground forest, making them ecological islands. The altitude causes them to have a different climate from the ground forest. The top presents cool temperatures with frequent rainfall, while the bases of the mountains have a tropical, warm and humid climate. The isolation has led to the presence of endemic flora and fauna through evolution over millennia of a different world of animal and plants, cut off from the rest of the world by the imposing rock walls. Some tepui sinkholes contain species that have evolved in these "islands within islands" that are unique to that sinkhole. The tepuis are often referred to as the Galapagos Islands of the mainland, having a large number of unique plants and animals not found anywhere else in the world. The floors of the mesas are poor in nutrients, which has led to a rich variety of carnivorous plants. The weathered, craggy nature of the rocky ground means no layers of humus are formed. The tepuis, also known as 'islands above the rainforest', are a challenge for researchers, as they are home to a high number of new species which have yet to be described. A few of these mountains are cloaked by thick clouds almost the whole year round. Their surfaces could previously only be photographed by helicopter radar equipment. Humans have still yet to set foot on many of the tepuis.

Most tepuis are in the Canaima National Park which has been classified as a World Heritage Site by UNESCO.

A few of the most notable of the Tepuis:

Auyan-tepui is the largest of the tepuis with a surface area of 700 km². Angel Falls drops from a cleft in the summit.

Mount Roraima, also known as Roraima Tepui. A report by the noted South American researcher Robert Schomburgk inspired the Scottish author Arthur Conan Doyle to write his novel The Lost World about the discovery of a living prehistoric world full of dinosaurs and primeval plants. The borders of Venezuela, Brazil and Guyana meet on the top.

Matawi Tepui, also known as Kukenan, because it is the source of the Kukenan River, is considered the "place of the dead" by the local Pemon Indians. Located next to Mount Roraima in Venezuela.