Uplift

Between 50 and 70 million years ago, an ancient fault was reactivated during a time of tectonic activity, lifting the layers to the west of the fault over 7.000 feet higher than those to the east. Rather than cracking, the rock layers folded over the fault line. Continued lift occurred again some 20 million years ago.

All information about the Waterpocket Fold was obtained from this PDF document from the National Parks service.