ACTIVITY: Modeling Plate Movement

The activity below draws from the content in the page EXPLORING PLATE TECTONICS.

Phenomenon:

Volcanic eruptions are common in Hawaiʻi (Fig. 1)!

Fig. 1. Lava flows on the island of Hawai'i. (Image courtesy of GIPHY) — Fig. 1. Lava flows on the island of Hawai’i. (Image courtesy of GIPHY)

Inquiry:

Where does lava come from?
Why do volcanic eruptions happen mostly on Hawai’i island?
How did the Hawaiian Islands form?

Guiding Questions:

What is the evidence that the land on earth is moving?
Where did the lava that formed the Hawaiian Island chain come from?

Activity:

Discover how geologic features form by modeling the slow movement of Earth’s tectonic plates.

Note: This activity has Further Investigations below (an interactive game, crossword puzzle, and plate labeling sheets) to help solidify understanding of vocabulary.

Materials:

Part A. Model:

Deck of cards, or tangrams
Shaving cream
Small pebbles
Spatula or wooden spoon
Towels for clean up
Baking pan, tub, or wide bucket
Mesh mat or screen
Student Worksheet and Teacher Guide (attachment below)

Recommendations:

This activity can be done using edible ingredients (like graham crackers or cookies for plates and cool whip or pudding for magma).
For the mesh or screen, a roll of ‘no slip’ shelf liner works well.

Part B. Map:

Map of Earth’s plates overlay (attachment below printed on clear acetate)
Extra sheet of clear acetate
Dry erase markers
World map showing seafloor features (attachment below)
(Note: this is more effective when printed in color)

Recommendations:

There are two ways to do the map activity:

Print the map of Earth’s plates on clear acetate so that it can be placed over the world map, or
Print the map on plain paper and cut out each of the plates. Students can then try to connect the plates back together on top of the world map with seafloor features. (Note: You may also laminate the map of Earthʻs plates before cutting and then use the plates instead of cards or tangrams in the model portion of the activity.)

Procedure:

Fig. 2. An example of plate movement model. What will happen to the shaving cream layer when the cards move apart? What about when they move together? (Image by Kanesa Duncan-Seraphin)

Part A. Prepare and Explore Your Model

Follow your worksheet to set up and conduct your trials.
Squirt a layer of shaving cream into the bottom of the pan or tub (Fig. 2).
Use your spoon to flatten the shaving cream so it’s evenly distributed.
Gently place two of your plates on top of a pile of magma (shaving cream) so that they form a rectangle.
Conduct your trials.

Trial #1: Divergence

Before testing the plate movements, describe what you think will happen when you pull the plates apart.
Very slowly, push down and gently slide the two plates apart.
Record what happened on your worksheet.

Trial #2: Convergence

Clean your plates and place them back on top to form a rectangle.
Describe what you think will happen when you push one plate under the other.
This time, push one plate down and under the other plate.
Record what happened on your worksheet.

Trial #3: Transform Fault Movement

Clean your plates and place them back on top to form a rectangle, this time leave a small space between the plates.
Push down on the plates so a bit of magma comes up between.
Put a few small pebbles on the magma in between the plates.
Describe what you think will happen when you slide the plates in opposite directions along side each other.
Gently slide the plates in opposite directions along side each other.
Record what happened on your worksheet.

Trial #4: Island Chain Formation

Fig. 3. Model demonstrating hot spot formation. What will happen when the shaving cream squirts up through the mat? (Image by Sebastian Stewart)

Set aside the model of convergent and divergent plates to prepare a new model for island chain formation.
Using the mesh material (remember, this also represents one of Earth’s plates), hold it flat and free from any surface.
With help from another partner, hold the can under the plate and point it upwards (Fig. 3).
Describe what you think will happen when magma (shaving cream) squirts upwards through the plate (mesh material).
Gently squirt a small amount of magma three times (stay still as you squirt the can!) and slowly move the plate after each squirt.
Record what happened on your worksheet.
Challenge: see if you can recreate the Hawaiian Island Chain!

Part B. Compare your model to a map of Earth’s features

Using what you’ve learned in this experiment, take out the world map, clear acetate sheet, and map of Earth’s plates overlay (printed on clear acetate).
Look at the world map and see if you can identify any plate boundaries where convergence, divergence, or transform movement may occur. (hint: start by looking in the middle of the Atlantic Ocean)
Place the clear acetate sheet on top of the map.
As best as you can, trace the plate boundary in the middle of the Atlantic ocean.
Continue tracing areas that you think are potential plate boundaries.
Place the map of Earth’s plates overlay in between your trace layer and the map to compare what you’ve traced with the official plate boundaries.
Continue tracing plates, using the map and plate overlay as a guide.
Record your observations on your worksheet.

Activity Questions:

Name one thing you have learned about Earth’s features from this activity.
Where do earthquakes generally occur?
Are the Hawaiian Islands on a plate boundary?
Why does Hawai’i have more volcanic activity than some other locations on Earth?
What is a hot spot?
How did the Hawaiian Islands form?