(Geomorphology)

A klippe is a type of allochthon, a section of a geologic thrust sheet that has, through the vagaries of deformation and erosion, become separated from the main body of the sheet, or nappe. Between the rocks of the klippe and the surrounding footwall rocks is an unconformity created by the now-inactive thrust fault. Due to the nature of overthrusting, the underlying rocks are frequently younger than the rocks on top.

It is frequently difficult to tell the difference between a nappe ("main body") and a klippe ("remnant"), and the status of some klippen is controversial. Occasionally, the nappe is entirely gone, leaving only klippen as evidence for its existence.

Klippen are interesting to geographers because out-of-place rocks erode into soils atypical of the soils around them, providing environmental variations supporting different types of plant and animal life.

As the name may suggest, the term was invented by German and Swiss geologists studying the Alps, which were created from strenuous folding and overthrusting.

Klippen can appear anywhere there has been overthrusting followed by erosion. A few well-known places where klippen can be found are:


       klippe             nappe

           _           ___________________
     __/\_/ \__       /
    /          \     /  <- thrust <- 
  ==============\___/======================
                
             (side view)


       _______       |
      /       \     /     /    /
     |  /   \  \    |  /    /
    /      \    |   |     /    /
   |  /   \  \  |   |  /     /
   |    klippe  |   |     nappe
   \  \  \   /  |   |
    |   \  /   /    |  /      /
     \  \   / /     /   /  / ___   /
      \______/     /       _/   \__
                  |  /    /        \
                   \  /  | fenster /
                    \    \___   __/
                     \  /    \_/
                      \
                       |  \   /
                       /         \
                      |  /  /
                      \

            (top view)

Inspiration for the diagram is drawn from Figure 7-18 on page 168 of
Chorley, Richard J., et. al. Geomorphology (Methuen & Company, 1984, New York ISBN 0-416-32590-4).