Alaska GPS Analysis

Robert Butler (University of Portland) and ANGLE Project


This activity introduces students to high precision GPS as it is used in geoscience research. Students build "gumdrop" GPS units and study data from three Alaska GPS stations from the Plate Boundary Observatory network run by UNAVCO. They learn how Alaska's south central region is "locked and loading" as the Pacific Plate pushes into North America and builds up energy that will be released in the future in other earthquakes such as the 1964 Alaska earthquake.



This activity can be done with introductory geoscience learners in secondary school or early college.

Skills and concepts that students must have mastered

Learners should be familiar with plate tectonics and earthquakes. The instructor should definitely give a brief introduction to GPS systems at the start of the activity if the students are not already familiar.

How the activity is situated in the course

This activity would probably be best midway or late in a unit on plate tectonics and earthquakes or geoscience and hazards.


Content/concepts goals for this activity

Students will be able to:
  • Diagram and describe the basic components of the GPS system and a GPS station
  • Construct a small model GPS station
  • Interpret high precision GPS data

Higher order thinking skills goals for this activity

  • Calculate tectonic velocities from GPS time series data and graph resulting vectors
  • Synthesize results from three GPS stations to determine the implications for future earthquakes in south central Alaska.

Other skills goals for this activity

Description and Teaching Materials

See attached file for educator notes, NGSS alignment, links to supporting resources, student exercise, and answer key.
Alaska GPS Analysis Activity (Acrobat (PDF) 1.2MB May20 18)

Two similar activities featuring Pacific Northwest GPS data are available from the Cascadia EarthScope Earthquake and Tsunami Education Program (CEETEP)

Teaching Notes and Tips

See above educator notes.


Formative assessment of student understanding can be gathered from classroom observation and discussions with individuals or small groups.
The student exercise serves as the summative assessment for the activity. Some questions have clearly correct answers. Teachers can develop a simple grading scheme for open ended questions such as two points for thorough and correct answer, one point for partially correct, and zero for incorrect.

References and Resources