Geology of the Grand Canyon

What is the age of the rocks at the base of the Grand Canyon?

• 80 million years

• 1.7 billion years

• 500 million years

• 5.5 million years

What type of rocks are found at the base of the Grand Canyon?

• Vishnu shist

• Sandstone

• Shale

• Limestone

What evidence suggests that ancient mountains once stood where the Grand Canyon is now?

• Calcium content in rocks

• Garnets found in rocks

• Alignment of pebbles in riverbeds

• Fossils of sea animals

What caused the uplift of the land in the Arizona region?

• Glacial activity

• Erosion

• Tectonic plate collisions

• Volcanic activity

When did the Colorado River arrive in Arizona?

• 1.7 billion years ago

• 500 million years ago

• 80 million years ago

• 5.5 million years ago

What evidence suggests that the Colorado River arrived in Arizona?

• Alignment of pebbles in riverbeds

• Muddy death of a lake

• Presence of sea fossils

• Formation of limestone

How old is the Grand Canyon?

• 5.5 million years

• 80 million years

• 500 million years

• 1.7 billion years

What caused the Colorado River to carve out the Grand Canyon?

• Erosion

• Tectonic plate collisions

• Glacial activity

• Volcanic activity

What is the dominant color of the rocks in the Grand Canyon?

• Light

• Dark

• Buff

• Red

What is the significance of the alignment of pebbles in ancient riverbeds?

• Indicates the presence of fossils

• Determines the age of the rocks

• Indicates the direction of water flow

• Determines the type of rocks present