About one-third of the earth's landmass is desert or semi-desert. These regions have unique geological features not found in humid environments. These features are most often caused by wind and water erosion in the stark desert environment. The picture you see below shows the long term effects of weathering.

The theory in hand is that for the past 600 million years, the land that today is Red Rock Canyon National Conservation Area was at the bottom of a deep ocean basin. The variety of marine life that lived and died in those waters left behind deposits of shells and skeletons more then 9,000 feet thick. Those deposits, after thousands of years of pressure on them, formed limestone and similar carbonate rocks. Around 225 million years ago, crustal movements caused the seabed to rise. Mud and sand was deposited which was later consolidated into shales and marine sandstone. As the land changed sea levels trapped large bodies of water, which evaporated, leaving behind layers of salt and gypsum. Some of the mineral-rich sediments, after being exposed to the atmosphere, became oxidized and turned the red and orange you see today in Red Rock Canyon.

Also included in the formation of this area were the deserts. About a 180 million years ago the Red Rocks area was completely arid, much like the Sahara Desert. It was a giant dune field that stretched from Nevada to Colorado. The wind shaped the sand, creating and leveling giant sand dunes. This constant changing created "crossbeds" in the sand, layers of sand from the constantly changing. The shifting sands were covered by other sediments and then cemented into sandstone by iron oxide with calcium carbonate. This is known as the Aztec sandstone, which is extremely hard. It forms the prominent cliffs of the areas.

The interesting thing about the Red Rock Canyon is that the oldest rocks in the Canyon are resting on top of the youngest ones. The reason this happens is the tectonic plates that make up our earth shift, and the compressional forces drive the crustal plates over the top of each other. Throughout the canyon, you can see the older, gray carbonate rocks of the ancient ocean over the red and orange sandstone created by the sand dunes. Many of the mountains in the area have very jagged, steep cliff faces to south and gentle rising slopes to the north because of the tectonic plates shifting the way that they do.