12.113 | Fall 2005 | Undergraduate

Structural Geology


Course Meeting Times

Lectures: 2 sessions / week, 1.5 hours / session

Labs: 2 sessions / week, 1.5 hours / session

Course Description

The course introduces mechanics of rock deformation. It discusses recognition, interpretation, and mechanics of faults, folds, structural features of igneous and metamorphic rocks, and superposed deformations and introduces regional structural geology and tectonics. Laboratory includes techniques of structural analysis, recognition and interpretation of structures on geologic maps, and construction of interpretive cross sections.


Introduction to Geology (12.001), Applications of Continuum Mechanics to Earth, Atmospheric, and Planetary Sciences (12.005)

Required Text

Twiss, Robert J., and Eldridge M. Moores. Structural Geology. New York, NY: W. H. Freeman, 1992. ISBN: 9780716722526.

Lab Information

“Labs” for this course serve two main purposes: first, they are a chance to discuss material covered during the week, answer questions, and supplement the lecture materials; second, they consist of exercises that apply material covered in lecture and reading to various problems.

There are 10 lab assignments. Apart from a few labs that will focus on specific techniques of structural geology (3D geometry, stereonets, Mohr circles), the labs will be based on geological maps and real data. If you are taking 12.114 (Field Geology), the experience you gain in this course will serve you well as you put theory into practice out in the mountains.

Labs will meet for 3 hours per week. At the beginning of each class, you will be given a mini-quiz. This will take 10 minutes, and we will correct them immediately. The mini quizzes will cover material from the lectures and ensure that everyone is more or less on the same page before beginning that week’s lab assignment. Then we will begin to work on the practical exercises for that week.

Ideally, most of the work will be done in-class. You may have to spend some time outside of class ensuring that you hand in clear and well-presented material. Group work is encouraged during lab meeting times, but you are responsible for the work you hand in.

Lab Grading

Labs make up 25% of your grade, but you must pass the lab portion of the course to earn credit for the course, i.e. No matter how well you do on the midterm and final exam, you still need to pass the lab. Lab assignments are due at the beginning of the next weeks lab. The week after that (one week after you turn them in) we will return old labs and hand out the answer key. Late assignments will be docked 10% each day after the due date. I will not accept assignments more than one week overdue. Extension may be given in exceptional circumstances, but you need to clear it with me as early as possible.

Labs will be graded according to clarity of expression, grammar, and good scientific style. Just writing down “the right answer” is usually only enough for a barely passing grade. (Note that since most of the questions will be worked on in class time, you will, in most cases, already be armed with the answers. Your work will consist of thoughtfully articulating these results.)

Lab Materials

You will want to have the following materials on hand:

  • Pencil(s) - thin (0.5 or 0.3 mm lead) mechanical pencils are best.
  • Pen - black ink, fine point, quick drying (so you don’t smudge it). Rapidographs are the best, but they cost a lot, so buy something cheaper instead.
  • Colored pencils - don’t bother getting anything expensive, and you don’t need 10,000 colors either. The best are the “Col-Erase” eraseable colored pencils.
  • Protractor and Ruler - essential. Make sure your ruler does metric.
  • Compass - for drawing circles, not a magnetic compass.
  • Graph paper - with a metric grid to cut down on the frustration.
  • Tracing paper - I’ll supply some, but you may want your own stash as well. The best is to get semi-transparent metric grid paper. This stuff is pretty hard to find, so I will try to get some.
  • Calculator - Doesn’t have to be fancy, but it should be able to do trig.


Labs 25%
Midterm Exam 25%
Final Exam 50%
Learning Resource Types
Lecture Notes
Activity Assignments with Examples