Review activity – stereonets & folds
Spring 2011
In the field, you measured strike & dip at several place on the top & bottom of a folded
layer.
Location
Top layer, left limb
Top layer, right limb
Bottom layer, left limb
Bottom layer, right limb
Strike
306
315
298
28
Dip
50 SW
31 SW
Vertical
10 NW
1
Plot the measurements on a stereonet
2
Is the fold cylindrical?
3
What is the fold axis?
4
Sketch the fold (include N)
5
How would you describe the fold? (tightness, Fleuty, roundness, orientation)
6
Is the top of the layer or the bottom more tightly folded? Use your stereonet
to defend your answer (interlimb angle of the tighter fold is an acute angle)
7
Which rock type, quartzite or shale, is the folded layer more likely to be?
Why?