Sunday, May 13, 2012

Not all the Rocks in Grand Canyon are Flat...

It is sometimes too easy to fall into a perceptual trap when confronted by a place as amazing as the Grand Canyon. The Spaniards who first saw the canyon in the 1500's thought it was maybe a thousand feet deep, and the Colorado River only 6 feet wide. Going from viewpoint to viewpoint, one might think that the layers of the canyon are uniform...and flat.

There are some important exceptions, which to me is what makes each viewpoint unique and interesting. For instance, if you walk to the east from Grandview Point, you can catch the Sinking Ship, and see that large structures offset or bend the Paleozoic layers of the canyon. This is an example of a monocline: a fold in which sedimentary rocks are draped over a fault like a rug thrown over stairsteps. This is part of the Grandview-Phantom Monocline. It formed in the late Mesozoic Era (the dinosaurs) during a regional disturbance of the crust called the Laramide Orogeny. The orogeny also produced the Kaibab Plateau, the highland through which the Grand Canyon was carved.
Wi-fi is tricky when camping. I think the McDonalds crew wants me to vacate our table...we've been here an hour, and we have to hit the road anyway. Until next time!
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