Contginental drift is so slow, in human terms its unnoticeable.

The Afrrican rift valley estends north, forming the Red Sea, clear up into Israel. The Dead Sea is a land depression of the tectonic event. Every year hundreds to thousands of small earthquakes are recorded there. Most too small to notice.

A building built on a fault fracture will be slowly torn apart. Nothing can stop it.

Colorado has such a rift valley in formation the San Luis. Every year the Sangre de Cristo and San Juan ranges distance from each other by a few millimeters. It has formed a mountain valley almost as large as the state of Massachusetts.



The Sangre de Cristo range is the eastern rim of the rift, and in a nook between the main range and the Blanca massif is Great Sand Dunes National Park, with the world's tallest (officially measured) sand dunes, up to 1200 feet tall. In the photo above you see the whole thing as one enormous barchan dune being swept up by wind against the base of the Sangre de Cristo range. Everything to the left of the mountain range is the San Luis Valley, a dry, flat, arid sandy desert.

There are hot springs all over these mountains, and warm artesian springs in the valley. A tilapia farm there brought in some alligators to dispose of tilapia remains, and the gators naturalized. About 4000 live year round in the warm artesian water, where air temperature in winter can drop to -50F.





In the southern end of the valley, the Rio Grande tumbles into the actual rift itself; the Rio Grande Gorge.