The Geology of Oregon's Painted Hills

The John Day Fossil Beds National Monument is a rich geologic complex that range in ages from the present to around 100 million years ago.

The Painted Hills are one of the Seven Wonders of Oregon. They are comprised of brightly-colored banded clay deposits from a series of volcanic ash eruptions during the Oligocene Epoch, about 35 million years ago.  

The colored bands represent changes in climate that occurred during composition.