1. Folded mountains: Large ridges and valleys with steep sides are formed when continental plates collide. Compressional forces may push rock layers upwards into long ridges, called anticlines, and create corresponding troughs, called synclines.

- Examples: The Himalayas, The Alps

2. Thrust Faults: Compressional forces can cause rock layers to be pushed over each other, forming large overthrust faults. Blocks of Earth’s crust are pushed horizontally above adjacent blocks, creating uplifted, tilted rock layers stacked over older rocks.

- Examples: The Lewis Overthrust in Montana, Zagros Mountains in Southern Iran

3. Dome Mountains: Uplifted, arched structures in the Earth’s crust created when large plumes of magma rise from the mantle. The magma exerts pressure to create broad, dome-shaped mountains of igneous and metamorphic rock.

- Examples: The Black Hills in South Dakota, The Adirondacks in New York.