Mountain Building

Mountain Building

Mountains are formed when tectonic forces push, fold, or uplift rock layers over millions of years. This process, called mountain building, happens due to the movement of tectonic plates. There are three main ways mountains form:

• Folded Mountains – Form when compression forces push rock layers together, causing them to bend and rise.
• Fault-Block Mountains – Form when tension forces pull the crust apart, causing large blocks of rock to rise or sink.
• Volcanic Mountains – Form when magma erupts and builds up over time, creating volcanic peaks.

Scientists can learn more about plate tectonics, earthquakes, and how the Earth's landscape changes by understanding how mountains are created.

Science and Engineering Practices (SEP): Developing and Using Models

Scientists use models to study how mountains form and change over time. They can track how tectonic forces shape mountains by analyzing satellite images, seismic data, and rock layers. 3D models and computer simulations help scientists understand plate collisions, fault movements, and volcanic activity contributing to mountain formation.

Activity Ideas:

• Mountain Building with Towels – Use two folded towels or pieces of fabric to simulate folded mountain formation. Slowly push the ends together to see how layers bend and rise, just like rock layers under compression.
• Volcano Model Demo – Create a simple volcanic mountain using clay and a bottle to simulate magma flow. When the “magma” (baking soda and vinegar mixture) erupts, observe how the layers build up to form a volcanic mountain over time.

Crosscutting Concepts (CCC): Cause and Effect

Mountains form when powerful tectonic forces cause the Earth's crust to bend, break, or uplift. These forces occur at plate boundaries, where crustal plates collide, pull apart, or slide past each other.

• Cause: Compression pushes rock layers together.
  Effect: Folded mountains, like the Himalayas, form where tectonic plates collide.
• Cause: Tension pulls rock layers apart.
  Effect: Fault-block mountains, like the Sierra Nevada, form as large blocks of crust are uplifted or dropped down.
• Cause: Magma erupts from beneath Earth's crust.
  Effect: Volcanic mountains, like Mount St. Helens, form as lava builds up over time.