Photo By/Credit
Michael Melford/National Geographic SocietyDate Shot/Created
03/27/2023Media Usage Rights/License
Copyrighted, All Rights Reserved - Used by Permission
Image
The basalt and granite boulders now littering the Ephrata Fan were carried there by torrents of water that gushed out of a canyon called the Grand Coulee. The largest piece of rock is more than 25 feet tall.