Picture/Photo: Weathered ash hummocks and sagebrush-covered slopes. John Day Fossils Bed National Monument, Oregon, USA

Weathered ash hummocks and sagebrush-covered slopes. John Day Fossils Bed National Monument, Oregon, USA

Weathered ash hummocks and sagebrush-covered slopes. John Day Fossils Bed National Monument, Oregon, USA John Day Fossils Bed NM