Wednesday, November 21, 2007

Four fossils form
1. Cover up :
The dinosaur lies on the mud in shallow water, which keeps scavenging animal away.

2. Rot set in :
Sediment starts to settle on the dinosaurs body. Meanwhile, bacteria attack the body's soft
parts, making them rot away.

3. Dead and buried :
After hundreds of years, the bones are safely buried beneath the surface. Water
seeps into the bones, leaving behind minerals that help to turn the bones into fossils.

4. Finished fossil :
As a sediment piles up, pressure grows. After thousands of years, this turns the sediment
and fossils into rock.

What are the best places to find fossils?
Fossils are found in rocks such as chalk, limestone, sandstone and shale. These were formed long ago by sediments building up on the seabed or at the bottoms of lakes. They are called 'sedimentary rocks' Rocks form by volcanic action, such as granite and basalt, do not contain fossils. You can find fossils where sedimentary rocks are being cut away by erosion, such as in sea cliffs or river gorges.

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