May 9, 2005. Bryce Canyon National Park, Utah. The reason this rock hold up well as does the rock in the Grand Canyon is because of the dry climate that does not encourage erosion. If I may point out, the Grand Canyon, is deep because of the erosion of a river. Sedementary rock unless it is a Sandstone, when it is deposited as shales such as seen here in the foreground is highly erodible when exposed to water. Valley and Ridge structures exist because the valleys erode while the ridges don't. Shale vs. Sandstone. The very top of the foreground is highly erodible sedimentary rock. The layer just beneath that which is marginally thick could be although not completely certain, but, it could be a sandstone and less erodible. The point here is that allowing Climate Change is a very bad idea.
