coal formation
Snemalna Knjiga Besedilo
- Trees fall down near a muddy swamp and sink to the bottom of the muddy swamp water
- Mud collects at the bottom of the swamp and stops the plants decaying
- The whole area is flooded by the sea
- Layers of sand collect on the sea bed, building up and creating enough pressure to turn the sand layers into sandstone and the mud layer into mudstone.
- The heat from the earth and the pressure from the mudstone and sandstone turn the dead trees into coal.
- Millions of years later coal is burned to release energy in power stations. This releases harmful gases into the atmosphere.
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