Petrified Forest
Arizona is a dry place. While something like seventeen prehistoric oceans have at one time or another been where Arizona is, you'd be excused for not noticing that today. However, remnants of those wetter times pop up every now and then.
This is petrified wood. When trees grew here in a swamp and were fossilized, the surrounding minerals entered the wood, turning it to stone with a wood pattern.
The Blue Mesa Badlands. The place is exactly as inhospitable as you would expect from the photo.
This area wasn't all bad, all the time. Once, pueblo indians lived here. Their carvings can be seen on stones.
In the north end of the national park is the Painted Desert. The desert was formed via erosion of the many layers that were laid down when seas were covering this place.