Book 1, Question 71
Why Do Canyons Get So Deep? Rivers, Rock and Rising Land!
Canyons are amazing cuts in the land. Rivers start small, but over time moving water wears away rock and soil, and the land beneath can slowly lift upward, so the river carves even deeper. Harder rock resists erosion and forms steep walls while softer rock wears away. The page says the Grand Canyon is more than 1,800 meters deep in places. Trickle water down a sand pile to see how a tiny river carves channels.
From the book
Page from A Million Whys Book 1
More fun facts
- Following the Colorado River, the Grand Canyon is about 277 miles long, up to 18 miles wide, and about 1 mile deep.
- The Grand Canyon was carved mainly by the Colorado River and other wearing-away forces over about the past 6 million years.
- It is really a big network of canyons connected together.
- Its steep walls show many layers of rock, like pages in a history book of Earth.
- The Yarlung Tsangpo gorge in Tibet is about three times deeper than the Grand Canyon, more than 3 miles deep in places.
- Mars has a canyon called Valles Marineris. It is about 2,400 miles long and up to 5.8 miles deep, the largest known canyon in the solar system.
- People have lived in the Grand Canyon area for thousands of years. Artifacts show hunting there about 12,000 years ago.
Sources: NASA Science, NASA Science
Questions kids ask
How deep is the Grand Canyon?
About 1 mile deep, and about 277 miles long following the Colorado River.
What is the biggest canyon in the solar system?
Valles Marineris on Mars. It stretches about 2,400 miles.