Activity Summary: Students will be able to use a model of an ocean sediment core to understand how the orientation of magnetic minerals is recorded in rock layers and relate this to real-world data showing polarity reversals over Earth’s recent history.

This lesson has students use an interactive that will demonstrate how a compass reacts to Earth’s magnetic field at different locations on Earth. They will then model an ocean core to understand how Earth’s magnetic field has been recorded throughout Earth’s history. Before beginning this lesson, students should have some understanding of plate tectonics and Earth’s magnetic field.

This lesson has been revised and updated based on Magnets at the Core.