Geology
The desert in Southern Utah contains geology that is unique to the rest of the world. The arches, fins, slot canyons, spires, and other red-rock formations you'll see in and around Moab represent hundreds of millions of years of geologic evolution. From being covered by oceans to the dramatic arches of today, the geology of the Moab area has a long and complex story to tell.
More than 500 million years ago, oceans covered most of the area that is now southern Utah. An deep basin of water now known as the Paradox Basin is where modern-day Moab is located. As millions of years passed, oceans would alternately cover and recede from Paradox Basin. Every time an ocean receded, it would leave a layer of limestone; every time it receded, it would leave layers of salt and shale.
Over a long period of time, after incarnations as mud plains and Sahara-like desert, these layers formed the foundation for the unique geology you see around Moab today. Each geologic period brought with it unique materials to form rock with; you'll see evidence of these periods in the layers found in many arches and towers today, in places like Bartlett Wash in Arches National Park and Slickrock.
The fins, towers, arches, and other formations in the area were created when cracks and erosion weakened less solid layers of sandstone, making room for wind and weather to hollow them out in artful ways.
Look for what look like hollowed-out bridges (arches), rows of tall, parallel rock slabs (fins), thin fingers of tall rock (towers), balanced rocks, and other incredible formations as you explore the fascinating geology in the Moab area.