1. Chapter 8 Worksheets
Section 1-4

2. 8-1 After You Read:
Complete the table by describing evidence that has been used to support the continental drift hypothesis and the theory of plate tectonics.
Hypothesis or Theory
Supporting Evidence
Continental drift hypothesis
Theory of plate tectonics
Similarities in shapes of the continents; same fossils and distinctive rock formations found in South America and Africa; climate change evidence.
Location of earthquakes and volcanoes; magnetism of ocean floor; age of ocean floor.

3. 8-2 Complete the graphic organizers to explain the processes that take place at a subduction boundary and a divergent boundary.
Molten rock
rifts or cracks
Oceanic
continental
Molten rock
Deep-sea trench
Deep-sea trench
Volcanic islands
Mountain chain
Moves away

4. Cause of plate movement
8-3 After You Read
Complete the table by listing three hypothetical causes for plate movements. Identify the type of boundary associated with each. Put a plus or minus sign next to the factors most or least influential on plate movement.
Cause of plate movement
Type of boundary
1. Mantle convection
Divergent boundary
2. Slab pull
3. Ridge push
Subduction boundary

5. 8-4 After You Read Mountain ranges far from plate boundaries today.
Data about ages of rocks.
Fossils
Evidence of glaciers in lands that are now tropical.

6. 8-4 After You Read Deep-sea sediments Igneous rock River sediment
Terranes