Question

how are coal and petroleum formed?

Answer 1

Coal and petroleum are formed  of dead animals and plants which has been subjected to various biological and geological process. Coal is the remains of trees, ferns and other plants that lived millions of years ago. ... Bacteria attacked the dead remains and changed them into oil under high pressure.

Answer 2

❤$\bold{Hi \: There!}$..❤

◾This process is actually called carbonisation.

$\underline{Knowing \: \: more \: \: about \: \: this..}$⤵⤵

⭐About 300 million years ago the earth has dense forests in low lying wetland areas. Due to natural processes, like flooding, these forests got buried under the soil. As more soil deposited over them, they were compressed. The temperature also rose and they sunk deeper and deeper. Under high pressure and high temperature, dead plants got slowly converted into coal. As coal contains mainly carbon, the slow process of conversion of dead vegetation into coal and petroleum is known as Carbonisation.⭐

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