Grand Canyon, AZ (2)

Sandy and I have been taking a theme trip inside a theme trip for the last few days.  The big theme is of course "Route 66", but the little theme has been the Harvey Houses.  In the last few days we have stayed at La Castenada, visited the Painted Desert Inn (now a National Park Museum, temporarily closed because of COVID), stayed at La Posada, and now staying at El Tovar.  All Fred Harvey hotels and all except the Painted Desert Inn designed by Mary Colter.  I'm already imagining a future trip via rail visiting these sites.  

The history of the Grand Canyon is complex, and not all the answers are certain.  But the basics which are well understood can be remembered by the nemonic "DUDE".  D=Deposits:  the great interior sea that at one time covered just about all the land between the Rockies and the Appalachians and collected layer upon layer of sediments over time to become sandstone and limestone.  U=Uplift:  As the Pacific plate sub-ducted beneath the North American plate, the North American plate rose, so far more than a mile and still rising forming the Colorado Plateau.  D=Downcutting: The proto-Colorado, and then the Colorado river itself began cutting into these uplifted sedimentary rocks.  E=Erosion:  The river, plus wind plus rainfall plus freezing and thawing deepened and widened the canyon until now at the base of the inner canyon the river has cut through all the sedimentary rocks and is now working on the metamorphic bedrock.  Awesome!  Today all we did was walk along the canyon rim and allow ourselves to be awestruck by views before us.