Paleomagnetism is the study of changes in Earth's magnetic field as shown by patterns of magnetism in rocks formed over time. It supports the theory of plate tectonics by showing that rocks can have normal or reverse magnetic polarity depending on their age and location, indicating movements of tectonic plates over Earth's surface throughout geological history. Evidence like paleomagnetism, seafloor spreading, earthquake patterns, and hot spots all provide support for the theory of plate tectonics.

1. Testing Plate Tectonics 9.4

2. PaleomagnetismThe study of changes in Earth’s magnetic field, as shown by patterns of magnetism in rocks that have formed overtime.

3. Normal PolarityA magnetic field that is the same as that which exists in the present.

4. Reverse Polarity A magnetic field opposite to that which exists at present.

5. Hot Spot A concentration of heat in the mantle capable of producing magma; which rises to Earth’s surface.

6. Key ConceptWhat evidence supports the theory of plate tectonics?Continental drift, seafloor spreading, palemagnetism, earthquake patterns, ocean drilling, and ocean hot spots.

7. Key ConceptHow does paleomagnetism support the theory of plate tectonics?By showing how Earth’s magnetic field affects rocks overtime.