Sandstone Slot Canyon

Sandstone Slot Canyon is an original illustration set in Colorado Plateau, USA. It lies in mid-latitudes, where the climate is hot desert — evaporation far outruns rainfall.

Tall smooth red sandstone walls curve inward like standing waves, close enough overhead to nearly meet. Fine horizontal sediment bands follow every curve. A narrow pale sand floor winds through the slot, and one small hard-edged opening of blue sky shows far above.

Why is the canyon this narrow and this smooth?

A canyon this narrow and this smooth is carved by flash floods, not by a permanent river: infrequent, violent, sediment-loaded water scouring the same joint again and again. The horizontal banding is ancient dune bedding turned to stone, which is why the rock is uniform enough to erode into curves. Red comes from iron oxide. The whole form requires thick sandstone and a dry climate that floods rarely.

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