Undergraduate introductory course in geoscience

Students should be introduced to metamorphic and sedimentary features.

We have used this activity as a homework assignment after the topic is introduced in lecture and reading, but it could also be used in class, in lab, or as group work.

Students will be able to identify metamorphic features (cleavage, boudinage, deformed clasts) in photographs.

Students will be able to interpret shortening/elongation directions from deformed features.

Students will be able to identify salient geological features in outcrop photos. Cognitive scientists refer to this skill as disembedding.

Students will understand that faulted rocks record dynamic geologic processes.

This worksheet focuses on identifying metamorphic features in outcrop photos, distinguishing them from sedimentary features, and going a step further to think about how metamorphic features were formed. For this worksheet, students are given 4 outcrop photos. The first two photos each contain a meta-sedimentary rock with a foliation fabric, the third photo contains boudinaged beds, and the fourth photo shows flattened clasts. In the first two photos, students are given a description of bedding and cleavage and asked to trace and label each feature on the photos. For the photo of boudinage, students trace the boundaries of 2 boudinaged layers and indicate the direction of elongation inferred from the geometry of the boudins. For the photo of deformed clasts, students draw the directions of maximum elongation and shortening for two clasts, assuming that they were originally round. After completing all of the tasks, students complete 3 multiple-choice questions.

This worksheet uses the sketch-understanding program with built-in tutor: CogSketch. Therefore, students, instructors, and/or institution computer labs need to download the program from here: http://www.qrg.northwestern.edu/software/cogsketch/. At any point during the worksheet, students can click the FEEDBACK button and their sketch is compared to the solution image. The built-in tutor identifies any discrepancies and reports pre-written feedback to help the student correct their sketch until they are done with the activity. Once worksheets are emailed to the instructor, worksheets can be batch graded and easily evaluated. This program allows instructors to assign sketching activities that require very little time commitment. Instead, the built-in tutor provides feedback whenever the student requests, without the presence of the instructor. More information on using the program and the activity is in the Instructor's Notes.

We have developed approximately two dozen introductory geoscience worksheets using this program. Each worksheet has a background image and instructions for a sketching task. You can find additional worksheets by searching for "CogSketch" using the search box at the top of this page. We expect to have uploaded all of them by the end of the summer of 2016.

CogSketch has a gradebook feature that allows instructors to batch grade worksheets using the defined rubric in the worksheet. Once graded, instructors can also open all the sketches and evaluate student work. Instructions are given in the Instructor's Notes.

Download CogSketch: http://www.qrg.northwestern.edu/software/cogsketch/