Soil: What's Under Your Feet? (Part 2)

What You'll Learn

Soil forms slowly from weathered rock mixed with decomposed organic matter. Different layers (horizons) form with topsoil on top, subsoil below, and bedrock at the bottom.

Key Words

sedimentary
earthquake

Materials Needed

cotton balls
food coloring
clear container
rocks

Safety First

Use materials only as directed in the experiment.
Keep small objects away from young children.
Work in a well-ventilated area when using vinegar or other strong-smelling substances.

Steps

Step 1 — Read

Study the diagram and label the parts you recognize.

Step 2 — Do

Create a timeline of Earth's history on a 5-meter strip of paper. Place major events (first life, dinosaurs, ice ages, humans) at the correct scale.

Step 3 — Observe

Observe what happens and describe it in detail.

Step 4 — Record

Record your observations in your science journal with measurements and descriptions.

Check Your Understanding

Question 1

1 of 3

What is a mineral?