First, Red Rocks is part of the Fountain Formation, which includes an arkosic conglomerate sandstone. It stretches from the Flatirons of Boulder, CO to the Garden of the Gods in Colorado Springs, CO. It was created as a result of the Rocky Mountain formation beginning in the Pennsylvanian-Permian age, about 300 million years ago. To understand how the Fountain Formation of Red Rocks was created you must understand how the Rocky Mountains were created. The Ancestral Rocky Mountains were formed when two plate tectonics converged with one another and one of the plates was subducted underneath the other. The erosion of this mountain range deposited sediments into the valleys and were compressed and buried over several years. Millions of years later, the present day Rocky Mountains formed from a process called folding, where layers of sediment in the land were compressed, causing a "ripple-effect". It then began to tilt and expose the underlying layer of sediment, which is the reason for the almost-vertical rock structures of the Fountain Formation you see today. (See "Ship Rock" and "Creation Rock") It lies upon ancient granite and gneiss. Chemical changes in the mineral, hematite, as well as iron oxides and feldspar grains are responsible for the reddish color of the rocks. Ship Rock and Creation Rock are two land-forms that helped to build the natural, outdoor amphitheater of Red Rocks that thousands of people get to take advantage of every year. And here's a fun fact, Red Rocks used to be listed as one of the Seven Wonders of the World... and then there was the discovery of Geography and more people went to college (haha).
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Ship Rock
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Creation Rock
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