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Sea-floor Spreading

Sea-floor Spreading

Author: Karisa Mantey

Explain how plate tectonics accounts for the features and processes (sea-floor spreading, mid-ocean ridges, subduction zones, earthquakes and volcanoes, mountain ranges) that occur on or near the Earth’s surface.

In this section, you will learn about sea-floor spreading.  Make sure to watch the notes screencast on sea-floor spreading before completing any of the activities.

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Sea-floor Spreading Notes

Watch this screencast about sea-floor spreading. Make sure to take notes while watching. Write down any questions you may have about sea-floor spreading on your note sheet.

Sea-floor Spreading Notes

Use this note sheet to take notes while watching the sea-floor spreading screencast.


Explaining How Continents Move

Read this nonfiction passage to learn more about Harry Hess and sea-floor spreading. While reading, make sure to use good reading strategies such as monitoring your reading, making connections, visualizing, and asking questions. As you read through the passage, answer the questions. The questions are critical thinking questions so you may not find the answer right in the text. Use your background knowledge and what you read in the passage to help you answer these questions.


Source: Earth Science Daybook

Sea-floor Spreading Made Easy

During this activity you will investigate sea-floor spreading and magnetic reversals. For this activity you will need to work with a partner or in a group of 3. Follow the instructions on the student worksheet to help get you started with this activity. Once you have read through the directions and are ready to begin the activity, call me over so I can help you with the lab.


Continental Drift Web

Watch this video to help you understand how to fill out the Continental Drift Web.

Continental Drift Web

On the Continental Drift Web you will see different pieces of evidence that support continental drift. You need to tell me how each piece of evidence supports the theory of continental drift. Write your response around the piece of evidence.


Continental Drift Writing Piece

You will be writing a five paragraph essay that explains the theory of continental drift and pieces of evidence that support it. Look at the student sheet for instructions and more information.


Constructed Response Questions

Answer the questions about sea-floor spreading in your constructed response questions packet.