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HangingLakeTrailHeadL
PARACONFORMITY: Hanging Lake area, Glenwood Canyon --- An unconformity occurs between the lower Ordovician Manitou Formation and the upper Devonian Chaffee Group. [The Manitou Fm extends left horizontally from the lone tree on the sloping skyline ridge in the middle of the picture. The formation is about twice as thick as the tree is high. The Chaffee Group is about the same thickness and is the next higher layer with many tree growing along the top of it on the skyline.] The 25 million year-long Silurian period is missing between them, although no evidence is found here for major erosion in the lower layer.
Trail06WtoRiver
PARACONFORMITY: Whirlpool Canyon, Dinosaur N.M. --- The Mississippian Madison Limestone forms the cliff about a third of the way up the canyon walls to the right of the Green River. Below it is the Cambrian Lodore Formation. In between the Ordovician, Silurian, and Devonian Periods are missing. The resulting unconformity is barely discernible although it represents a break of possibly 155 million years.
AngularUnconformity
ANGULAR UNCONFORMITY: Along Interstate-70, New Castle --- Rock layers were deposited, hardened, uplifted at an angle, eroded flat, and then more rock was deposited on top.