Coal - 1 of 10

Coal FAQs - 10 Found

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How did coal form?

Coal formed when prehistoric forests and marshes were buried and compressed over hundreds of millions of years. As time went on, moisture was squeezed out due to the heat, and pressure of the rock over it, leading to higher and higher concentrations of carbon (though other elements occur within coal, such as oxygen, sulfur, nitrogen), and harder and denser coal. This process resulted in the various types of coal seen today, which are ranked according to their moisture content and
concentration of carbon.

Tags: Energy, Mining, Geologic Time, Coal