It is the east side of Red Canyon that gives it its name. The curious fact is that the west side is completely different. The soil is not particularly red, maybe a little in spots, and the land sweeps away from the canyon road in a gentle slope with just a few dry cliffs because the soil is so weak.
How did this happen?
First of all, we need to look a little farther west, at the Wind River Mountains. These were built – that is, they came up from the earth – at the end of the Cretaceous. The Cretaceous is the third period of the Mesozoic Era (Triassic, Jurassic, Cretaceous). Now, to review: the red shales and siltstones date from the Triassic, and the pink sandstones from the Jurassic, and both were laid down flat, as sediments must be; you remember that Nicholas Steno explained this way back in the 17th century.
But then, in the Cretaceous, the third part of the Mesozoic, something completely different happened. The Wind River Mountains were born; they pushed upwards from below the landscape and tilted everything sideways. They lie just west of our canyon, and when they rose out of the earth, it was crumple time for everything. The sandstones held out best, but whenever they broke up and gave way, the silt and shale followed quickly, and whatever rivers formed on the new landscape took away all the debris, leaving what was under the Triassic soils.
Well, what’s under the Triassic is the Permian, the last period of the Paloezoic.
The Permian Phosphoria formation has some sandstones that are windblown (not river borne) and some limestones, which is to say underwater shell deposits, and some dolomites and other things. None of it is particularly red; it’s mostly white and gray, rather drab, a nice place to rest your eyes from the intensity across the road. So at the bottom of the canyon is Red Canyon Creek, which carried away the soft stuff; then on one side the Permian Phosphoria slopes away to the west, and on the other, the bright Chugwater leaps up towards the Jurassic Nugget on the eastern horizon. It’s two different worlds, dating from millions and millions of years apart, with a little creek and a little red road running between, and all sorts of gray-green sages and things that must notice the difference between the soils, but they just grow along as if time and soils made no difference at all.