Detecting Cascadia's changing shape with GPS | Lessons on Plate Tectonics part of Activities
Research-grade Global Positioning Systems (GPS) allow students to deduce that Earth's crust is changing shape in measurable ways. From data gathered by EarthScope's Plate Boundary Observatory, students discover that the Pacific Northwest of the United States and coastal British Columbia — the Cascadia region - are geologically active: tectonic plates move and collide; they shift and buckle; continental crust deforms; regions warp; rocks crumple, bend, and will break.

Episodic tremor and slip: The Case of the Mystery Earthquakes | Lessons on Plate Tectonics part of Activities
Earthquakes in western Washington and Oregon are to be expected—the region lies in the Cascadia Subduction Zone. Offshore, the Juan de Fuca tectonic plate subducts under the North American plate, from northern California to British Columbia. The region, however, also experiences exotic seismicity— Episodic Tremor and Slip (ETS).In this lesson, your students study seismic and GPS data from the region to recognize a pattern in which unusual tremors--with no surface earthquakes--coincide with jumps of GPS stations. This is ETS. Students model ductile and brittle behavior of the crust with lasagna noodles to understand how properties of materials depend on physical conditions. Finally, they assemble their knowledge of the data and models into an understanding of ETS in subduction zones and its relevance to the millions of residents in Cascadia.

Introduction to Graphing GPS data | Lessons on Plate Tectonics part of Activities
This activity emphasizes making graphs—in order to make interpreting graphs easier. Students graph data measuring how GPS stations move north or south and east or west. They begin by graphing fictitious data and progress to graphing data from several stations in the western United States. Eventually they graph north-south vs. east-west motion of a station in order to see that another purpose of plotting data is to make maps. They also develop intuition about vectors.