One by one, year by year, the layers accumulated on the bottom until the water shallowed and the basin was filled with striped mud. Each season the thickness of a light layer or a dark layer recorded what kind of a year it was, sunny, cloudy, or average. What seems remarkable to me is that 200 million years later, as the rock was squeezed and as the layers rumpled, the kind of year it was, the weather of some previous era, was noticed once again as each layer offered its own resistance to further change.

It's no wonder that this artful geometry, exposed in the banks of an arroyo, caught the attention of those who passed near. And it is no wonder that the patterns deserve notice. For within the harmonic pattern is an almost Einsteinian interweaving of space and time. Powerful atmospheric, and oceanic, and subcrustal forces were at work in making this example of nature's fretting. Its rhythms, now frozen in space, were orchestrated by the response of fluids to the earth's tilt and rotation. All these things together give our small piece of rock its tempo. I can count the number of folds in a layer and place that number on a musical score sheet. If I were to add flags and a clef, it could be a musical composition written by the earth.

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