Canyons, the spectacular landscapes on Earth, can evoke questions as you venture into their diverse types and experience the thrill they offer: What is a canyon? How is it formed? What are its types?

A canyon refers to a steep-sided valley with a depth greater than its width. Its main features include a cross-section often in a "V" or "U" shape, with a greater depth than width, steep slopes, narrow river (or stream) beds, and a high gradient along the riverbed, often featuring rapids and cascades.

How are they formed?

The formation of canyons results from the uplift of the Earth's crust and the erosive action of flowing water. Additionally, the type of rock and structural conditions play significant roles.

Hard and brittle rocks are prone to significant fracturing, facilitating downcutting by water and the formation of canyon landscapes. Therefore, the formation of canyons is a result of the complex interplay of multiple factors, leading to a kaleidoscope of canyon types and formations.

To simplify the categorization of canyons, geologists classify them into two main types based on the segment of the river and its morphology and geological stress differences: canyons in the upper reaches of the main river channel and canyons near the headwaters of river tributaries.

Let's first discuss canyons in the upper reaches of the main river channel. These canyons are characterized by large-scale, wide river surfaces, high flow rates, navigability, and primarily vertical erosion by flowing water. They often occur in uplifted areas between two faulted basins.

Canyons near the headwaters of river tributaries, on the other hand, exhibit characteristics of mountainous streams. They are narrower with steeper slopes, featuring a more pronounced "V" shape in cross-section. The longitudinal profile shows greater slope gradients, with deep pools and small waterfalls.

These canyons often accumulate large rock blocks from collapses on both sides and upstream. Compared to canyons in the main river channel, they have lower water volume, and faster flow rates, and are generally unnavigable. For example, the Maoling River Canyon in Xingyi, Guizhou Province, China, belongs to this category.

Do you know which is the most famous canyon in the world?

It's the Grand Canyon located in the United States, stretching 446 kilometers long, with an average width of 16 kilometers, and elevations ranging from 2000 to 3000 meters. The average depth of the canyon is 1600 meters, with a maximum depth of 1740 meters.

The Grand Canyon is formed by the incision of the Colorado River into the upraised "tablelands" of the Colorado Plateau in the southwest. The rock layers exposed in the canyon walls range in age from the Precambrian through the Cenozoic, displaying a variety of colors and textures.

The predominant rock formations consist of multicolored Paleozoic sandstones, shales, and limestones, exhibiting hues of red, yellow, purple, and brown, creating a vibrant and ever-changing landscape. Due to the prevalence of red sandstone and shale in the upper regions, it is also referred to as the "Red Canyon." Its overall shape resembles a box due to its average width of 16 kilometers, presenting a vast, grand, and awe-inspiring sight.

Canyons can whisper, soft to the bone, or they can be like waves, with a rugged vigor. These hidden canyons in the depths of the earth stand quietly beautiful throughout the ages. In the canyon, observe the peaks and rivers, and feel the magic and beauty of nature's creation!