Teach the Earth > Petrology > Teaching Activities > Compatibility Diagram 1: Dsp-Py-Qz-Ka-H2O

Compatibility Diagram 1: Dsp-Py-Qz-Ka-H2O

Dexter Perkins
University of North Dakota
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This activity was selected for the On the Cutting Edge Reviewed Teaching Collection

This activity has received positive reviews in a peer review process involving five review categories. The five categories included in the process are

  • Scientific Accuracy
  • Alignment of Learning Goals, Activities, and Assessments
  • Pedagogic Effectiveness
  • Robustness (usability and dependability of all components)
  • Completeness of the ActivitySheet web page

For more information about the peer review process itself, please see http://serc.carleton.edu/NAGTWorkshops/review.html.

This page first made public: Nov 9, 2009


One of three compatibility diagrams I use in class. This is a short activity to introduce students to compatibility diagrams (triangular diagrams showing stable assemblages) and how tie lines change when a reaction line is crossed. This exercise can, in turn, be followed by Compatibility Diagram 2 and Diagram 3.

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Required Petrology class – mostly junior level students

Skills and concepts that students must have mastered

Students need to be familiar with mineral reactions and their implications.

How the activity is situated in the course

This activity can be used to check understanding just after introducing the idea of compatibility diagrams.


Content/concepts goals for this activity

Students learn how to draw appropriate compatibility diagrams.

Higher order thinking skills goals for this activity

Other skills goals for this activity

Description of the activity/assignment

A 1-page in-class exercise on compatibility diagrams.

Determining whether students have met the goals

More information about assessment tools and techniques.

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