Mountain belts that are adjacent to active, convergent plate boundaries are still growing, as evidenced by active volcanoes, frequent earthquakes, and measurable changes in elevation. Analyzing the formation of active mountain belts can help us understand ancient mountain belts as well.

Geologic features such as folds, faults, and igneous rocks remain in place long after the period of active mountain building that formed them has ended. By comparing geologic structures in ancient mountains with actively growing mountains, we can deduce details about mountain-building processes that formed ancient mountains.

  !   Click each dot to see a photograph of geologic features associated with each mountain belt. Use the information to answer the questions below.

7. Describe the geologic features and their ages for each mountain belt.

8. Compare the Andes, Himalayan, and Appalachian Mountain belts. Describe features that are common to all three.