The Royal Arch – October 23, 2019
Earlier today, Ricardo and I did a 10k (6.22 mile) trail run in the Flatirons region of Boulder, Colorado. Total elevation gain was nearly 1,800 ft. (550 meters) up to a geologic formation called the Royal Arch, pictured here. The Flatirons are remnants of the so-called “Fountain Formation”, a mineral-rich sand that eroded from the ancestral Rocky Mountain uplift 300 million years ago.
Sediments were deposited in the area by inland oceans that came andwent through geologic time and were eventually compressed into sandstone. Then, 45 million years ago, they were thrust upwards with the same tectonic forces that created the modern Rocky Mountains.
The Royal Arch is a fragment of this exposed Fountain Formation and has been sculpted through time by water, wind and mechanical erosion into the formation we see today!