In-class review: folds


Short in-class review question about using given strike and dip information to classify a fold. Stereonets used.



upper-level structural geology class

Skills and concepts that students must have mastered

plotting strike & dip on a stereonet to determine fold axis, interlimb angles & cylindricity
fold classification schemes
ability to visualize strike & dip in 3D
understanding of rock competencies

How the activity is situated in the course

I've used these both as a quick review at the start of the class after fold classification schemes were discussed (the other material was covered earlier in the semester) and as an in-class quiz. Basically, these are meant to check & make sure students understand the material we just covered.


Content/concepts goals for this activity

deformation mechanisms
kinematic analysis
manipulation of data on a stereonet

Higher order thinking skills goals for this activity

analysis of data
visualization of data in 3D

Other skills goals for this activity

Description and Teaching Materials

Single sheet that I give to students to work on for 5-10 minutes at the beginning of class. Students should have access to stereonets in order to complete the problems.

Review -- folds (Microsoft Word 33kB Jun18 12)

Teaching Notes and Tips

I tend to encourage the students to work on the sheets alone to start with and then discuss the results as a group and let the students correct one another. I find that question 4 throws them almost every time.


I check verbally to see if all the students (its a small class <8) understand the correct answers and how they were derived. A similar problem was placed on the final, which checked retention over the course of the semester.

References and Resources