demonstrations:modelling_faults_with_layered_clay

Modelling Faults with Layered Clay

Materials: ★☆☆ Easy to get from supermarket or hardware store
Difficulty: ★☆☆ Can be easily done by most teenagers
Safety: ★☆☆ Minimal safety procedures required

Categories: Plate Tectonics

Alternative titles: Earthquake Fault Model

Summary

Clay layers are stacked and cut to represent the Earth’s crust along a fault line. By pushing on the edges, the clay buckles and slips, showing how earthquakes occur along faults.

Procedure

  1. Flatten three pieces of clay, each in a different color, into rectangles.
  2. Stack the clay rectangles on top of each other and press them together to represent Earth’s crust layers.
  3. Use a dull knife to cut through the middle of the clay stack, creating a model fault.
  4. Rejoin the pieces but offset them slightly so they don’t match up perfectly.
  5. Push inward on the outer edges of the clay stack and observe how the clay shifts and buckles along the fault, simulating an earthquake.

94605 Geological Faults and Folds Model (using a commercially available kit) - Artec Educational:


📄 Earthquake Fault Model - Cairns Regional Council: https://www.cairns.qld.gov.au/__data/assets/pdf_file/0011/469127/Fault-model-experiment.pdf

Variations

* Try using more or fewer clay layers to represent different crustal thicknesses.

  • Experiment with cutting the clay at different angles to show various fault types (normal, reverse, strike-slip).
  • Add pressure gradually vs. suddenly to compare slow movement vs. earthquake-like jerks.

Safety Precautions

  • Use only a dull knife to avoid injury.
  • Supervise younger students while cutting the clay.

Questions to Consider

  • What does the cut in the clay represent in the Earth?
  • Why does the clay shift when pressure is applied?
  • Where are the nearest fault lines to our location?
  • When was our region last affected by an earthquake?
  • What factors might cause an earthquake in our area?