Grand Canyon attracts the attention of the world for many reasons, but perhaps its greatest significance lies in the geologic record preserved and exposed here. The rocks at Grand Canyon are not inherently unique. Similar rocks are found throughout the world. What is unique about the geologic record at Grand Canyon is the variety of rocks present, the clarity with which they are exposed, and the complex geologic story they tell.
The Grand Canyon is stretched out in an area of 277 miles (446 kilometers) length, 18 miles (29 kilometers) wide and 1.83 kilometers (6000 feet) deep. John Wesley Powel who was an American Explorer, teacher, geologist and also a war veteran has described the Grand Canyon thus, "The glories and beauties of form, color, and sound unite in the Grand Canyon – forms unrivaled even by the mountains, colors that vie with sunsets and sounds that span the diapason from tempest to tinkling raindrop, from cataract to bubbling fountain."
How old is the canyon itself? The early history and evolution of the Colorado River (of which Grand Canyon is only a part) is the most complex aspect of Grand Canyon geology. We know that the erosion which has shaped the canyon has occurred only in the past five to six million years. This is only yesterday, considering the age of the rocks through which the river has carved.
Grand Canyon continues to grow and change. As long as rain and snow continue to fall in northern Arizona, the forces of erosion will continue to shape Grand Canyon.
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