Devil's Slide - Utah
Posted by: 
Hikenutty
N 41° 03.834 W 111° 32.870
12T E 453971 N 4545995
Devil's Slide is a limestone formation alongside I-84 that looks like a giant playground slide.
Waymark Code: WM1H3J
Location: Utah, United States
Date Posted: 05/08/2007
Views: 227
Devil's Slide is a limestone formation that looks like a giant playground slide. The slide is a great example of how rock layers of differing composition are affected by erosion.
The sides are composed of hard, dense limestone layers around 40 feet high, 25 feet apart, and several hundred feet long that seem to slide down the hillside. In between these hard layers is a softer, shaly limestone that's of a different composition. The middle layer is more susceptible to weathering and slowly eroded, leaving the slide shape we see today.
The Utah Geological Survey wepage for the slide says this about it:
This site is a tilted remnant of sediments deposited in a sea that occupied Utah’s distant geologic past. Approximately 170 to 180 million years ago, a shallow sea originating from the north spread south and east over areas of what are now Montana, Wyoming, and Utah. This sea extended as far east as the present-day Colorado River and south into northern Arizona.
Over millions of years, massive amounts of sediment accumulated and eventually formed layers of limestone and sandstone. In northern Utah, these rocks are known as the Twin Creek Formation and are approximately 2700 feet thick. About 75 million years ago, folding and faulting during a mountain- building episode tilted the Twin Creek rock layers to a near-vertical position. Subsequent erosion has exposed the near-vertical rock layers and created Devils Slide.
If you are interested in visiting Devil's Slide you will find it at a scenic viewpoint turnoff located near milepost 110 on I-84.