Cliff-former
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The term cliff-former is a geologic term indicating that a unit of bedrock is more resistant to erosion than overlying or underlying units and consequently outcrops have high slope angles. It is more or less equivalent to ridge-former, and may be contrasted with slope-former. In humid environments, sandstones are typically cliff-formers. In arid environments, limestones are often cliff-formers also. Recent extrusive igneous units may be cliff-formers as well.
In the Ridge-and-Valley Appalachians of the eastern United States the major ridge-formers are the Tuscarora, Pocono, and Pottsville Formations. [1]
[edit] References
- ^ Kempler, Steve (2007-01-19). Geomorphology : Chapter 2 Plate T-12 : Folded Appalachians. NASA, Goddard Earth Sciences (GES), Data and Information Services Center (DISC). Retrieved on 2008-03-16. “The major ridge makers are the Tuscarora (T), Pocono (Po), and Pottsville (Pt) Formations.”
