Soil Liquefaction and Earthquakes
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, Soil and Erosion
Alternative titles: Shaking Soils Activity
Summary
Students investigate how different soil types - sand, peat, and topsoil - respond to shaking when saturated with water. By placing a model “house” on each soil type and simulating earthquake motion, they observe liquefaction effects and determine which soils provide the most stability.
Procedure
- Form a hypothesis about which soil type will resist liquefaction best.
- Fill three shoebox-sized containers two-thirds full, one with sand, one with topsoil, and one with peat.
- Build a model “house” from Lego or other construction materials (about 8 cm x 10 cm).
- Add 1 liter of water to the first soil container (topsoil).
- Place the Lego house on top of the soil, then set the container inside a larger bin to allow shaking.
- Measure the height of the house from the soil surface to the roofline.
- With a partner, shake the larger bin side to side for 40 seconds without lifting it off the surface.
- Observe how the soil and house behave during and after shaking.
- Re-measure the house height and note any tilting, sinking, or shifting.
- Repeat twice more for the same soil, then test sand and peat in the same way.
- Record results in a data table and calculate averages.
Links
Liquefaction In Action - GeoscienceAustralia:
Demonstrate Liquefaction | Shaky Sediments - Science Snack Activity - Exploratorium Teacher Institute:
📄 Liquefaction - Earth Science Week: https://www.earthsciweek.org/resources/classroom-activities/liquefaction/
Variations
- Use houses of different weights to test whether heavier loads affect sinking.
- Change the amount of water added to see how saturation influences liquefaction.
- Experiment with soil mixtures (for example, sand mixed with clay).
- Try adding gravel or other stabilizers to see if they reduce shifting.
Safety Precautions
- Protect surfaces with a mat or tray to prevent scratching from sand grains.
- Handle containers carefully to avoid spills of soil or water.
- Wash hands after handling soil.
- Do not eat or put hands near the face during the experiment.
Questions to Consider
- How did each soil behave while being shaken? (Peat often compresses, sand may liquefy, topsoil may provide more stability.)
- Which soil caused the house to sink the most? Why?
- Which soil type provided the best stability for the house? (Likely topsoil, depending on water content.)
- What real-world implications does liquefaction have for buildings during earthquakes? (Foundations may shift or collapse.)
- How do engineers reduce liquefaction risk in construction? (By using deep foundations, soil compaction, or ground improvement techniques.)