The Cheyenne Belt is the tectonic suture zone between the Archean-age Wyoming craton to the north and the Paleoproterozoic-age Yavapai province to the south.
It was formed during the Paleoproterozoic Medicine Bow orogeny between 1.78 and 1.74 billion years ago when island arcs collided with the Wyoming craton.
[2] The Wyoming craton north of the belt is an Archean basement with a cover of younger miogeoclinal strata (sedimentary rock deposited on the passive margin of a continent.)
The Yavapai province south of the belt contains no Archean crust, and it is intruded by granitoid rock with radiometric dates between 1780 and 1630 Ma.
[4] The collision of the Yavapai arcs with the Wyoming craton began with in a mountain-building event from 1780 to 1750 Ma called the Medicine Bow orogeny.