Tracking Tectonic Plates Using Two Independent Methods

Laurel Goodell
Princeton University
Author Profile


Students use two independent methods to determine relative plate motions across a plate boundary. They find that plate tectonic theory generally holds up but also discover sophisticated detail (e.g. velocities aren't constant, internal deformation of plates occurs). NOTE: this activity is currently being updated and enhanced. Please contact the author for more information.

Used this activity? Share your experiences and modifications



This exercise is used for several introductory-level courses at the introductory level (Physical Geology, Natural Hazards). It could also be adapted for higher-level courses.

Skills and concepts that students must have mastered

Students should understand the basic tenets of plate tectonic theory, and understand the different types of plate boundaries.

How the activity is situated in the course

This is a two-week laboratory exercise that comes after lecture treatment of plate tectonics.


Content/concepts goals for this activity

Understanding tectonic plate motions, using vector algebra, understanding the azimuth convention of denoting direction, understanding velocity as distance vs. time, understanding long-term average vs. short-term "instantaneous" motions.

Higher order thinking skills goals for this activity

Understanding evidence forming the basis of a fundamental theory, formulating and testing a hypothesis using two independent methods, analyzing data, understanding long-term average vs short-term "instantaneous" motions.

Other skills goals for this activity

Using Microsoft EXCEL and Google Earth, using a web-based "Plate Motion Calculator," using GPS data.

Description of the activity/assignment

Students come to this activity familiar with the basic assumptions of plate tectonics. Using a Google Earth platform showing commonly accepted lithospheric plate boundaries as well as locations of GPS stations, students form a hypothesis about motions expected across a particular boundary. They then set about testing their hypotheses by plotting motion vectors using two independent methods.

Students use a "Plate Motion Calculator" to determine "model" rates of plate motion averaged over millions of years.

Students interpret GPS data as near real-time rates of plate motion. RESULTS Students find that in general, plate tectonic theory holds up. However, they also discover sophisticated detail – rates are not constant, internal deformation of plates does occur and some boundaries are "wider" than others. Student evaluations of the activity demonstrate that they feel engaged and empowered as they work with authentic data, and gain a sophisticated understanding of a fundamental theory as well as the process of doing science.

Determining whether students have met the goals

Students prepare written reports, which include figures which show plate motions that they have analyzed.

More information about assessment tools and techniques.

Teaching materials and tips

Other Materials

Supporting references/URLs