Paper models of transform faults

Ready-to-print templates for the transform-fault paper model used by J. Tuzo Wilson (Wilson, 1965) to understand the concept of transform faults and explain it to others (as described by Stewart, 1990 and  Earle, 2004) can be downloaded from here.  Both two-ridge-segment and four-ridge-segment versions are included, each in three different formats.

To view the models left-click on the link.  To down-load right-click on the link and choose the "Save target as" option.  The two-ridge model is also shown below, along with instructions on its use and some photos.

  GIF format Word Document PDF document
Two-ridge-segment models transform2.gif transform2.doc transform2.pdf
Four-ridge-segment models transform4.gif transform4.doc transform4.pdf

 To prepare the model cut along the fracture zone from point a to point b with a razor blade.  Fold the paper on either side of the fracture zone as indicated.  Make 90 downward folds at the four locations marked Fold down, and 180 upward folds at the two locations marked Pinch together.  The resulting model will now be about one-half as long as the original, and will have two folds of paper (the soon to be created sea floor) projecting down from the surface.  Students must work in pairs to operate the model.  One holds the ridge segments together by gently pinching each of the downward folds just below the surface.  The other holds the paper at either end (adjacent to points a and b) and slowly pulls the new sea floor out of the ridge crests.  See photos below.

 

Folded transform fault paper model
Transform fault paper model being pulled apart

The Fault Analysis Group at University College Dublin has a wide range of other paper models that are useful for understanding faulting.  Go to this website and click on "Paper Models": www.fault-analysis-group.ucd.ie

Earle, S., 2004, A simple paper model of a transform fault at a spreading ridge, J. Geosc. Educ. V. 52, p. 391-2.

Stewart, J A, 1990, Drifting continents and colliding paradigms, Indiana University Press, Bloomington, IN, 285 p.

Wilson, J T, 1965, A new class of faults and their bearing on continental drift, Nature, V. 207, p. 343-347.


Steven Earle, Geology Department, Malaspina University-College, Nanaimo, Canada

earles@mala.bc.ca  http://www.mala.bc.ca/~earles