You canyons exist on all continents, being sights beautiful and dangerous, forming deep valleys that can reach up to five kilometers in depth. They are usually found in areas where there are rivers.
Those rivers carve the rocks over millions of years, and they may or may not be in evidence, in this case, leaving only a trail in their wake. Canyons that have no water in their deep valleys, as climate change, over geological time, may have made the water go elsewhere or simply having made the spring disappear with the changes caused by external agents of modification of the relief.
See more: Plateaus - type of relatively flat relief located at high altitudes
What are canyons?
the canyons are very deep valleys with steep sides, well vertical. This depth, in some of them, can reach up to five kilometers, which makes an impressive and highly dangerous canyon.
in your valleys, there may be rivers, largely responsible for the existence of the valleys, but that do not sculpt the landscape by themselves. these vouchers are
depressions relatives, which, along the length of the canyon, form huge rocky walls that “count” the age of the relief, formed millions of years ago, over the geological eras of the planet.canyon formation
The formation of a canyon is still a great mystery for geology, but there are some chances. The depth of a canyon can be obtained through Law Suit erosivethat take hundreds of millions of years, being one of the wonders produced by geological time.
The hypotheses about the formation of canyons revolve around the movements of plates tectonics and the uplifting of certain areas, that is, when a site is “raised” by the force of tectonism.
When there is this uplift, the water that passes between the raised areas gain more space and slope to follow the course, which accentuates the erosive process. For millions of years, the watercourse, associated with wind and rain erosion, transform the relief in a large depression, with vertical rock walls on the side.
Through the uplifting of the land, the rivers gain speed and deepen their beds, as there is a decline in their course. With this, the walls are gaining height, and the valleys reach depths of up to five thousand meters in continental lands.
There are cases of rivers that dry up after thousands of years, turning the canyon into a rock formation, with steep walls and valleys without a watercourse, with only the river's wake.
Characteristics of canyons
Most canyons have impressive features, showing their gigantic formation compared to other landscapes. They are magnificent relief forms, shaped with the help of external (erosive processes) and internal (tectonism) factors of modification.
When we observe a canyon, we see the rock layers overlapping each other, which may indicate the “age” of the place. Each rock extract indicates a geological time when such rocks were deposited and/or transported by external factors, such as rivers and winds.
Canyon valleys are low-lying areas. atmospheric pressure, which may indicate the presence of winds, clouds and fog. In many canyons, the presence of mists at its most extreme peaks, making it both beautiful and frightening.
There is canyonssubmarines, as a kind of extension of the course of a river at the bottom of the sea. These canyons have a formation process similar to continental canyons, but with the difference that they are submerged.
Many canyons have meandering, meandering rivers. Its rocky cliffs are ideal for hiking, climbing and exceptional photography, showing a fascinating landscape.
Read too: Plains - type of relief that is normally flat and with low altitudes
canyons in the world
the canyons are present on all continents of the planet, being a form of relief much appreciated by lovers of extreme sports, such as abseiling and climbing. Let's look at some examples of canyons around the world.
Examples of canyons in the world
One of the most famous is located in the U.S, O Grand Canyon, Arizona. This canyon was formed by the action of the Colorado River, one of the largest on the west coast of the country. In this state there is Coyote Buttes, a canyon with sedimentary rocks fragile, but with a beautiful look, which makes the entry of tourists limited.
Also in North America, We have the glen canyon, in Utah, United States, and the Sumidero Canyon, in Chiapas, in the Mexico.
At the African continent, O blyde river canyon, in Mpumalanga, in the South Africa, stands out for being the second largest on the continent, with 26 kilometers in length.
At Asia, O Kali Gandaki Canyon, at the Nepal, located among the Himalayan mountains, draws attention with its gorges and trails, attracting practitioners of rafting Worldwide.
already in Europe, the Gorge du Verdon canyon, in France, attracts tourists in search of kayaking and climbing. This canyon is 25 kilometers long and reaches depths of up to 700 meters.
Canyons in Brazil
O Brazil, for having the largest number of rivers in the world, is a territory with fantastic canyons, many within areas of environmental/permanent preservation, because concentrate springs of the most important freshwater reservoirs in the world. Let's look at some examples of Brazilian canyons.
Examples of canyons in Brazil
In the state of Sergipe, we found the Xingó Canyon, located 200 kilometers from Aracaju. This canyon has crystal clear water, which makes it one of the most visited places in Sergipe territory.
O Bandeirinhas Canyon, in Belo Horizonte, is within a preservation area, the Serra do Cipó National Park. In addition to lush trails, there are small natural pools for the joy of miners and tourists from other parts of Brazil.
At the Rio Grande do Sul is one of the most famous canyons in the country, in the city of Cambará do Sul. The Serra Geral National Park is the border between that state and Santa Catarina, forming magnificent walls. One of these is the Churriado Canyon and Fortaleza Canyon, both in the same park, forming a breathtaking landscape, with depths of up to 900 meters.
Still in this state, we have the Monte Negro Peak, located in the canyon of the same name, being the highest point in Rio Grande do Sul, with 1403 meters of altitude.
Also access: Difference between weathering and erosion
solved exercises
question 1 (Fuvest) The Fernando de Noronha archipelago, the islands of Trindade and Martin Vaz and the São Pedro and São Paulo rocks are Brazilian oceanic islands. Considering that these islands have no relationship with the continental relief, it is correct to say that their origin is linked to:
a) uplift of failed blocks
b) tertiary folding
c) underwater volcanism
d) sea level rise
e) coral accumulation
Resolution
Alternative C. Unlike canyons, oceanic islands form from undersea volcanic eruptions over millions of years. Most canyons have their formation contributed with the uplift of the plates, in addition to erosive processes, such as fluvial erosion.
question 2 (Fatec) Check the correct alternative about the work of external agents in the formation of the land relief.
a) Erosion is the wear of rocks generated by weathering or by the action of wind and water.
b) Tectonism results from the movement of magma under the earth's crust, producing faults, folds and seismic shocks.
c) Chemical weathering produces mechanical disintegration of rocks and is mostly found in hot and cold desert areas.
d) The erosive action of winds is more intense in tropical regions, due to the large number of storms throughout the year.
e) Volcanism is one of the main means of land relief construction, responsible for a large number of islands in the so-called “fire circle”.
Resolution
Alternative A. Erosive processes erode rocks and sculpt the most varied landscapes, such as mountain ranges, hills and canyons. Over millions of years, the continuous wear caused by erosions, which can be windy (winds), pluvial (rain) or fluvial (rivers), causes impressive landscapes formed naturally.
By Attila Matthias
Geography teacher
