The Sun's Anvil

People associate these formations with super dry climates, when in fact these formations occur only where there was once water on clay-like soil. When the water recedes, the sun evaporates the water and the clay shrinks. The deeper the rifts, the deeper the water had penetrated the soil. Doesn't mean it's always dry, just means it's dry for now.

Grand Falls of the Little Colorado, Arizona, when the falls weren't flowing.