Ever Changing Earth
What Force Causes Plate Movement?
The Most Powerful Force in the World?
By this point...
...we have observed changes in the Earth's surface, followed the data collected by past scientists, and collected our own data on the occurrences of major geologic events. All of this has led to the understanding that the Earth's surface is constantly being reshaped over long periods of time. The question that still remains is, what causes these changes? Critics of the The Theory of Continental Drift thought that there was no force powerful enough to move the continents around.
What do you think?
Learning Targets
- Students will predict the outcome of a demonstration.
- Students will make careful observations during a demonstration.
- Students will analyze results and make inferences about plate movement
Success Criteria
- I have predicted the outcome of a demonstration.
- I have made careful observations and collected data on a data table.
- I have analyzed the results and made an inference.
Roles
- Organizer, Materials Manager/Technician, Time Keeper, Checker, Reader
MS-ESS2-2. Construct an explanation based on evidence for how geoscience processes have changed Earth's surface at varying time and spatial scales.
Purpose
The purpose of this activity is to use a model of the layers of the earth to infer a cause for the movements of the plates.
Demonstration
Procedures
- Copy the following chart into your Science Notebook - Convection in the Mantle Observation Chart
- In this demonstration you will observe as two different colors of food coloring are dropped in either side of a tank of water. The tank is set up with a heat source in the middle at the bottom. (see the diagram below)
- Predict the outcome of the demonstration. What will happen and why do you think it will happen?
- Observe the demonstration by the teacher or watch the following video. If you are viewing a live demonstration, starting with an initial observation, make rough diagrams of your observations every 45 seconds for a total of 3 minutes and 45 seconds. This will give you six diagrams.
*If you are watching the video only (because it is sped up) once the demonstration begins, pause to make observations every 10 seconds. You will need to watch up to the 1 minute and 30 second mark.
Observations and Inferences
- What observations did you make during the demonstration?
- What inferences can you make about the observations that you made?
Going Further
- How are molecules, density, and gravity related to what you observed?
As a Team
- Create a group diagram that shows how convection in the mantle results in the movement of earth's tectonic plates.
- Share your diagrams with the other teams and add to yours.
- In the above video, stop at 2 min 48 sec and add anything that you missed.
Animation
View this animation that shows how convection in the mantle results in the movements we see at plate boundaries.
