Chapter 27, Problem 7TE

To determine

Whether the metamorphic rocks are found at all three types of plate boundaries.

Answer to Problem 7TE

The metamorphic rocks are usually found at convergent plate boundaries.

Explanation of Solution

Metamorphic rocks form when rocks change after undergoing extreme pressure or temperature increase. These temperature changes must be hot enough to reorganize matter within the rock but not hot enough to melt it. Hot magma pushes itself to the surface at both divergent plate boundaries and convergent plate boundaries. This magma comes in contact with rocks as it rises to the surface. The magma is hot, heating the rocks around it. As the rocks heat, they change and become metamorphic rocks. This process is called contact metamorphism.

Regional metamorphism occurs at convergent plate boundaries due to intense pressure as two plates collide, the Earth's crust folds and faults. The intense pressure changes large areas of the Earth's crust into metamorphic rock. Mountain ranges are typically metamorphic rock due to plate tectonic processes.

Conclusion:

Therefore, metamorphic rocks are usually found at convergent plate boundaries.