Coal is a fossil fuel that is formed from the remains of plants that lived and died millions of years ago. Over time, the plantmaterial was subjected to heat and pressure, which caused it to transform into coal.
Types of Coal
There are four main types of coal:
Anthracite: This is the highest quality coal, known for its high carbon content and low impurities. It is often used for heating and in the steel-making process.
Bituminous: This type of coal is widely used for electricity generation and in industrial processes. It has a higher heat content compared to lignite and subbituminous coal.
Subbituminous: Subbituminous coal is used primarily for electricity generation and has a lower heat content than bituminous coal.
Lignite: Lignite is the lowest quality coal, with high moisture content and low heat content. It is used mainly for electricity generation.
Formation of Coal
Coal is formed through a process called coalification. It begins with the accumulation of plantmaterial in swamps and marshes. Over time, the plantmaterial is buried by sediment and subjected to heat and pressure, which causes it to undergo physical and chemicalchanges, ultimately turning into coal.
Earth/Space Science: Students will use scientific skills and processes to explain the chemical and physical interactions (i.e., natural forces and cycles, transfer of energy) of the environment, Earth, and the universe that occur over time.
Earth History: Explain how sedimentary rock is formed periodically, embedding plant and animal remains and leaving a record of the sequence in which the plants and animals appeared and disappeared.
Explain how sedimentary rock buried deep enough may be reformed by pressure and heat and these reformed rock layers may be forced up again to become land surface and even mountains.