Mon Prof Augmenté
From Bone to Stone
A dead dinosaur can become a fossil if it is buried in mud or sand very quickly. Over millions of years, minerals slowly replace the bone until it turns to stone.
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Age 9: open this week
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In the picture
- A dinosaur bone: minerals have replaced the hard bone and turned it to stone.
- Thick layers of sand and mud: they covered the body fast and pressed down for a very long time.
- Water moving through the ground: it carries minerals into the buried bone.
Examples
- A leaf pressed in mud can leave a fossil shape.
- A seashell buried under beach sand can slowly turn to stone.
Key takeaways
- Quick burial protects a body from rotting or being scattered.
- Fossils form very slowly, over millions of years, as minerals replace body parts.
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