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How is coal formed? |
| Answer» \tThe formation of coal takes millions of years, which is why it is an exhaustible and non-renewable natural resource.\tIt\xa0was formed around 300 million years ago when the earth was covered with swampy forests.\tWhen plants in these forests- mainly trees, mosses, ferns, and reeds died, they fell into the swamps.\tThus there was a thick layer of dead vegetation in the swamp formed.\tAs years passed, more and more plants died and many such layers were formed, one above each other.\tThe topmost layers compressed the layers below. Heat and pressure caused some physical and chemical changes and eventually, some carbon-rich deposits were formed. | |