Planet Earth - Coal

Coal seams are found in many places around the world.


Ancient trees and other plants lived, died and were fossilised.

The formation of a coal seam of one metre thickness required approximately 100 metres of plant material.
All those plants took carbon dioxide out of the atmosphere. 
Some larger coal seams are, for example, 10 metres thick.

They took around 40,000 years to form, but have been mined and burned in a little over 100 years.

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