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What are fossil fuels?

An oil tankerAn oil tankerFossil fuels include coal, oil and gas. They are formed from the remains of living things that died millions of years ago. Planes, vehicles and power stations all give off exhaust gases from burning these fuels. These add billions of tonnes of carbon dioxide to the atmosphere, which contributes to global warming. Oil and gas are used as a fuel in power stations, cars, ships and aircraft, but they are also essential for many chemical industries.

The formation of coalThe formation of coal

Formation of coal

Coal began to form about 350 million years ago in the Carboniferous Period. At that time, vast areas of the Earth’s surface were covered with swamps where trees and giant ferns grew. When these plants died, they rotted down and gradually changed into a dark soil called peat (1). As the centuries passed, the peat was buried under layers of sand and mud (2).

As these layers pressed down more and more tightly on the peat, it eventually turned into hard, black, shiny rock: coal (3). Folding of these rocks has brought some coal layers close to the surface (4).

The second tallest freestanding structure in the world (after the Burj Khalifa tower in Dubai) is the Petronius oil platform in the Gulf of Mexico. Only 75 metres (246 ft) of it shows above the sea surface, but it descends 610 metres (2001 ft) to the ocean floor.

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