grand canyon/earth history

The rock at the bottom of the canyon is how old?

The age of a rock compared to the ages of rock layers

How long is the Grand Canyon?

Rocks on the top are typically?

The canyon became a park in what year?

This theory proposed all the continents had merged into one before.

Oldest known fossils come from what?

Which president greatly admired the Grand Canyon?

Scientist who studies fossils

The age of a rock given as the number of years since the rock formed

The Grand Canyon is in what state?

What river runs through the Grand Canyon?