Rock Layers and Fossils Grand Canyon

How deep is the gorge carved by the Colorado River in some places within the Grand Canyon?

• Less than a mile deep

• Exactly one mile deep

• More than a mile deep

• Up to 18 miles deep

Approximately how old are the oldest exposed rocks in the Grand Canyon?

• Millions of years old

• Hundreds of millions of years old

• Nearly two billion years old

• Half the age of the universe

Which geological law states that younger rock layers are found on top of older rock layers?

• Law of Original Horizontality

• Law of Cross-Cutting Relationships

• Law of Lateral Continuity

• Law of Superposition

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What does the Law of Original Horizontality state about how rock layers are initially deposited?

• They are deposited vertically due to tectonic forces.

• They are originally deposited flat due to gravity.

• They are always found in a folded or bent shape.

• They are formed by volcanic eruptions.

If a fault cuts through several rock layers, what does the Law of Cross-Cutting Relationships tell us about the age of the fault relative to the layers?

• The fault is older than the layers it cuts through.

• The fault is the same age as the oldest layer it cuts through.

• The fault is younger than the layers it cuts through.

• The fault's age cannot be determined relative to the layers.