Unconformities are depositional contacts between rocks of greatly different ages. Consequently, they represent an equally amount of missing rock record. Because most unconformities form by erosion, they may signify periods of mountain building.

Key to photos below:
All nonconformities are labelled by their location only. Angular unconformities are labelled by "Ang". Disconformities and Buttress unconformities are described as such.

Click on any of the images below to see a larger view.

Ang. Siccar Pt.

Grand Teton, WY

Grand Cyn.

Grand Cyn.

Ogden, Utah

Buttress uncon.

N. Wisconsin

Ang. N. Wash.

Colo. Spgs., CO

Ang. Death
Valley, CA.

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