How Long Does it Take to Make a Canyon?

Yellowstone Canyon
Yellowstone Canyon
Yellowstone National Park is one of our great American treasures. During several summers at Montana State University, we spent a lot of time wandering around this huge wilderness. Most people think of Old Faithful and the geyser basin when they think of Yellowstone, but the canyon and falls are some of Yellowstone’s most beautiful places.

What does it take to make a canyon like this, and what does this tell us about the history of the Earth? The answers to these questions are remarkably simple. You need something that is capable of cutting down through a material, and you need a material that can be cut. On planet Earth, the primary geologic cutting agent is water. When water is frozen, it gouges and cuts a wide U-shaped channel. This is called a glacier, and the shape of its canyon is easy to identify. In the liquid form, water makes a V-shaped channel like the Yellowstone Canyon. How long the channel is and how deep it is cut are determined by how much water flows, how long it flows, and how hard the rock is. In Yellowstone, most of the rock is geyserite, a soft yellow rock easily cut and eroded by water. This soft rock is produced by volcanic processes, and deep canyons can happen quickly when flooding occurs.

In other places like the Grand Canyon and most of the eastern part of the United States, the rock is much harder and takes much longer to erode. Yellowstone is a young topography caused by recent volcanism. The sedimentary rocks of the eastern United States and the Grand Canyon took a long time to deposit and a long time to erode. All of this points to God’s patience and timelessness. We should not try to lock God into a time-frame that makes God look small and trivial. Remember that “one day is with the Lord as a thousand years, and a thousand years as one day” (2 Peter 3:8).
–John N. Clayton © 2017