Grand Canyon National Park: A Colossal Beauty

Name: Grand Canyon National Park (United States of America).
Location: in the state of Arizona, 60 miles east of Las Vegas, Nevada.
Area: 1,218,229 acres.

The Grand Canyon and the Colorado River

In 1540, a bunch of Spanish soldiers led by captain Don Garcia Lopez de Cardenas, lieutenant of Vazquez de Coronado's expedition, wants to find the mythical treasures in Cibola and Quiriva, in the current state of Arizona. Suddenly, their march is interrupted by a profound and endless trench, in the bottom of which, flows a river of red waters. Due to this huge obstacle, the captain prefers to look into the more favorable lands in New Mexico.

In 1776, the Spanish missionaries Francisco Hermenegildo Cortes and Silvestre Velez Escalante arrived to the villages of the Havasupai Indians, whose hunting territories reached the southern upper edge of the Grand Canyon. After a brief evangelization task, ill and dejected, they decided to abandon these landscapes, known in that age as Terra incognita (unknown territory.)

Until 1857, it wasn't carried out a real exploration of the Colorado River. Joseph Ives cycled up the river from its mouth until the enlargement of Lake Mead. The descriptions and experiences of this pioneer provoked an authentic commotion among scientific organizations. So, in 1869 the Natural History Society of Illinois funded the scientist John Wesley Powell's expedition to finally reveal the secrets which continued to be hidden by that remote place in Arizona. The original work that collects the discoveries made in that journey, "Canyons of the Colorado" by John W. Powell, despite including lots of subjective impressions and unimportant avatars, became the mandatory starting point for numerous intellectuals before arriving to the Grand Canyon.

The public recognition of the natural values of the Grand Canyon justified its declaration as National Monument in 1908. 11 years later, the United States Congress passed the Act that gave birth to the Grand Canyon National Park, a protected zone of a total of 673,599 acres which later would be extended to the current 1,218,229 acres in 1975.

Inside the Colorado River

It is in vane any attempt to describe the Colorado Grand Canyon. The fantastic grandiosity of its multiple gorges, escarpments and naked ochre grooves can't simply be described in words, no matter how many adjectives and superlatives were used. However, a few digits could approach us to the amazing dimensions of the Grand Canyon: here, the Colorado River has excavated, along 275 miles, gorges with up to 7,000 feet in depth and variable width, which goes from 650 feet, where the river is not visible from the edges of the grove, to 20 miles. These numbers make the Grand Canyon the largest emerged gorge in the planet.

Beauty is not the only characteristic of the Grand Canyon. The area is presented as a weird example of the collision between two powerful telluric forces, the orogeny and the fluvial erosion. As a result, the rocky walls of the Grand Canyon enclose an authentic geological chronicle, in which you can read a story of transformations dating back to two billion years. Like we have just said, two are the main characters in this epic: the earth and the river.

Exploring the Past

2 billion years ago, in the turbulent Pre-Cambrian age, hardened carbonates with lavas and other eruptive products were compressed and transformed very slowly into metamorphic rocks. The resulting formation, known as Vishnu shales, triggered the formation of huge mountains which reached altitudes up to 30,000 feet high, for later being eroded and reduced to high plains. As a remainder from that age, the lower walls of the Grand Canyon (up to 1,500 feet above the river level) are made up of very dark-grey shales, in occasions interrupted by red streaks of feldspar and other heavy minerals. This layer, which lacks fossil remains, is prolonged hundreds of feet inwards the earth and reflects the oldest rocks of the Canyon.

Later on, these lands got depressed and flooded by marine waters, to later being filled up with sedimentary layers with a thickness of thousands of feet. To this phase belong the Bass limestones and the violet quartzites of Shinume. These sedimentary layers resulted in mountains which, following a new erosive cycle, ended up losing height and giving way to a depression. For the second time, the marine waters flooded these lands, leaving their fossilized brachiopods and trilobites remains.

The use of radioactive isotopes, allows scientists to reconstruct with high precision the story of the Canyon throughout the last 600 million years. The brown sandstones of Tapeat, the greenish clays from Brigt Angel and the reddish lands from the Mississippian Period tell us that the marine occupation of these lands ended 280 million years ago. From then, the waters withdrew, so the sandstones of the Supai Esplanade and the red shales of Hermit enclosed fossils of archaic ferns, conifers and primitive insects that abandoned the swamps to start the conquest of the air.

The most modern layers of the Grand Canyon are, at least, 200 million years old (to get you an idea, the age of the European Alps is just 25 million). They talk about a new marine occupation and about a posterior elevation phase, that took place 70 million years ago, modeling the 6,500-feet-high mountains. Later, erosive phenomena reduced these levels down to appreciable levels nowadays.

Over the described geological substrate, started the excavating task of the Colorado River 25 million years ago, from the large ice sheets accumulated in the Rocky Mountains. The process speeded up 1 million years ago, when a harsh interglacial period allowed the meltwater from the glaciers to multiply by several times the level of the river and, as a consequence, its eroding powers.

This exposition is very far from being definitive when you are trying to explain the magnitude of the eroding process that reflects the Grand Canyon. In other words: there's no proportion between the erosive capacity of the river, no matter how large its volume became, and the cyclopean erosive work done by this. The Colorado River, foreign to the controversies that emerge from the scientific world, continues with its eroding process. It is estimated that the Colorado River pulls out 40,000 daily tons of sludge and other materials. Before installing the dams which regulate its volume, the river kinetic powers were able to pull out up to 380,000 daily tons!

The Edges of the Canyon

Going from one edge of the Canyon to the other by road, implies a displacement of more than 180 miles. The climate conditions in the two edges are very different, both because of the distance that separates them and their different orientation. These facts provoke the existence of a highly diverse wildlife, flora and fauna in the Canyon landscapes. For example, we have to look at the botanic richness of the area that encloses 5 of the 7 main described vegetation zones of all North America, besides having different exclusive types of these grooves.

In the same way, the Grand Canyon serves as shelter to numerous endangered animal species, like the bald eagle, the Californian brown pelican or the barn owl. The Colorado River also has two exclusive species of fish that inhabit its waters. We cannot forget the reptiles, incredibly well represented in these lands, highlighting the always dangerous rattlesnake.

Remote Arizona

Joseph Ives, the explorer who adventured into these lands in 1857 said in his diary: "What gets me sadder is that this remote beauty will remain unknown for the man forever." A century later, the Grand Canyon is visited by millions of people every year. The southern edge has a large crowd, where you can find all sorts of services and a hanging road which allows the access to strategic points for the contemplation of the Grand Canyon, for example, the Mather Point, Yavapai Point, Powell Memorial or Hopi Point. Authentic armies of RVs impose their laws for these roads, sometimes staying weeks inside the National Park.

Despite the park's popularity, the Park Administration has prevented the deterioration of the Canyon. All infrastructures are located in the upper plateaus of the southern and northern edges, while the Canyon per se keeps the same aspect it had when the first adventurers came in the 16th century. The words that pronounced president Theodore Roosevelt in 1903 have become a reality up to this date: "In the Grand Canyon, Arizona has a natural wonder which is in kind absolutely unparalleled throughout the rest of the world. I want to ask you to keep this great wonder of nature as it now is. I hope you will not have a building of any kind, not a summer cottage, a hotel or anything else, to mar the wonderful grandeur, the sublimity, the great loneliness and beauty of the canyon. Leave it as it is. You cannot improve on it. The ages have been at work on it, and man can only mar it."

Source: Wikipedia

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