This creek in Waterton Glacier, Montana cuts into a geological rupture structure. The crack narrows leaving space for the creek only. These rock formations contain the whole variety of an archaic ocean. 2500 million years old ripple marks can be found that formed in the sand by pounding of the waves in the shallow water close to an ancient beach.
Pentax K2, Pentax 28mm, f/22, 1sec, Kodak Ektachrome E6, ISO 100, tripod