“How was the Grand Canyon formed?” is perhaps the most common question that visitors ask when they first come to visit this breathtaking sight in Colorado, Arizona, U.S.A. One cannot help but wonder how the canyon was shaped to become such a gigantic wonder of nature. Geologists have put forth many theories to explain the formation of the Grand Canyon. However, all of these theories are scientific guesses – it is impossible for anyone to know for sure how it actually happened, because the formation took millions of years, way before the first people on Earth. Scientists can only guess what really happened. Nevertheless, modern knowledge of ecological processes gives some important clues about how the Grand Canyon was formed.
Formation of the Grand Canyon
• The rocks and soil that the Grand Canyon is composed of are also significant for finding some answers. It is a safe guess that various processes contributed to the creation of the Grand Canyon. Millions of years ago, a very tall mountain chain must have been occupying the exact area where the Grand Canyon is now. Erosion gradually flattened the mountains into a plain. Then the climate changes and seismic activity caused rocks to be deposited on the plain, layer by layer. Some of the rocks were eroded away, and some new layers were deposited again. The process continued, and perhaps it is still happening, unnoticed – because geological changes take place incredibly slowly, so it is impossible for people to perceive it.
• Geological processes that shaped the Grand Canyon were most probably erosions (mainly by water, possibly by ice as well, and to some extent by wind, too). Another contributing factor is the Colorado River. Continental drifts, volcanic activity, seasonal variations, climate changes and slight alterations in the earth’s orbit possibly played some role in shaping the Grand Canyon.
• Water is the force that outlined the Grand Canyon’s topography. Rain and floods chiseled the slopes of the canyon, taking down the soil and rocks quite easily. During very cold seasons, frozen water between cracks in the rocks helped to break them apart. Aided by seismic activity, rocks near the edges were easily dislodged, falling and settling into the sides of the canyons. Rock falls have been frequent, depositing debris in the Colorado River.
• An interesting observation is the difference between layers of rocks in the Grand Canyon. The rock layers are of different ages as well as types and places of origin. At the very bottom, forming the base of the Grand Canyon, you can see some incredibly old rocks. These rocks were part of the original mountain range that stood in the present location of the Grand Canyon. On top of them, as mentioned, there are layers of varied rocks. These subsequent layers may have been deposited by seismic activity and tectonic shifts under the earth’s surface.
• In summary, various geological processes molded the Grand Canyon into its present form. Erosion, seismic activity and seasonal changes are key factors. Perhaps the process is a continuing one, as the Grand Canyon proceeds to evolve.