Powell should be given the credit for the idea advanced in 1929 by Busk that a monocline is a double bend consisting of the anticlinal and synclinal bends. In the Colorado Plateau monoclines have an aggregate length of nearly 2500 miles, and the greatest nearly uninterrupted monocline is about 300 miles long. Every gradation from gentle open monoclines to overturned and thrust structures is present on the Plateau. Reversal of dip, either broad or locally abrupt, is common near the head or foot of the monoclines; however, the monoclinal designation should be retained on a regional basis. There is homology between monoclines and noses, anticlines, synclines, normal faults, and reverse faults.

The monoclines are thought to be tangentially compressive Laramide features, and in places they show pronounced coupling action. They are divided into a western group that may be genetically related to the Central Laramide Rockies and an eastern group related to the Eastern Laramide Rockies. Roughly dividing the two groups are the Uinta and San Juan basins and the Salt fold and fault belt of the Paradox basin.

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