Formed by the deposition of volcanic ash between 34 and 28 million years ago, the resulting layers mixed with soil and oxidizing metals to form the colorful and heavily eroded Painted Hills. The Painted Hills are one of three units in the John Day Fossil Bed National Monuments. Wheeler County, Eastern Oregon.

Formed by the deposition of volcanic ash between 34 and 28 million years ago, the resulting layers mixed with soil and oxidizing metals to form the colorful and heavily eroded Painted Hills. The Painted Hills are one of three units in the John Day Fossil Bed National Monuments. Wheeler County, Eastern Oregon.