What kind of rock is found at the lowest level of the Grand Canyon?

Elves Chasm gneiss

More than 1 billion years ago: The foundations are laid

Under extreme heat and pressure, their rocks transformed into the dark-colored “basement” rocks seen near the bottom of the canyon today — including 1.84-billion-year-old rocks called the Elves Chasm gneiss, the oldest known in the canyon.

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Explanation:

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explanation:

the answer is b. glad to .