How old is coal

About this free course 17 hours study. Level 2: Intermediate. Course rewards. Free statement of participation on completion of these courses. Create your free OpenLearn profile. Course content Course content. Energy resources: Coal Start this free course now.

Free course Energy resources: Coal. Previous 1. Next 1. Skip Your course resources Your course resources As you work through this course you will need various resources to help you complete some of the activities. Algae was around long before then in shallow seas, so there are coals made completely of algae that date back earlier than the Carboniferous.

The Carboniferous period MA saw the evolution of tall lycopod trees that accelerated the rate at which peat could be formed in tropical equatorial mires. High sea levels and a warmer climate also encouraged coal formation, by extending the area of coastal mires and other wetlands. Last year, researchers suggested that the evolution of white rot fungi — the fungus that breaks down plant lignin — at the end of the Carboniferous period may have slowed down coal formation.

But Bailey disagrees with this theory. It would be hard to distinguish any change in peat accumulation rate due to white rot fungi from the effects that climate change were having on peat. Peat continued to accumulate strongly throughout the Permian MA , when coalfields in the Hunter, Newcastle and Illawarra were forming. However it paused for a period at the Permian — Triassic boundary. About 90 per cent of all species on Earth were wiped out at this time. Once the plants recovered, coal formation began again.

This started with the recovery of spore-generated ferns, and a global "fern-spike". Land plants were unusually dominated by ferns until other plants regenerated. New York, U. Affolter, J. May 11, Geologic Overview [Online]. How Coal is Formed [Online]. May 12, Earth: Portrait of a Planet , 3rd ed. New York, NY, U. Kraushaar, R. Energy and the Environment , 2nd ed. Australia's black coal resources range from Permian to Jurassic in age to million years old , although most are Permian in age.

During this time, the climate was warm in Australia, and Eastern Australia, including the Sydney Basin was covered by large, meandering rivers, marshes, bogs and swamps. The sediments deposited in these environments eventually formed rocks such as shale, sandstone and coal.

Brown coal in Australia formed more recently than the black coals. These are mostly of Paleogene age 66 to 23 million years old. Coal is a sedimentary rock formed when abundant plant material is covered by sediments and the material accumulates faster than it can decay. The weight of the overlying sediments compacts the organic layers, increasing the temperature and pressure, which leads to physical and chemical changes to the plant material.

Water, carbon dioxide and methane are produced and escape, so the material becomes progressively enriched in carbon. With increasing time, and higher heat and pressure, the plant material first forms into peat, then is converted into brown coal, then sub-bituminous coal, bituminous coal, and lastly anthracite. Australia has the fourth-largest share of coal reserves in the world. Since the late s about million tonnes of black coal and about million tonnes of brown coal have been mined in Australia and the industry still provides significant employment, capital investment and domestic and export income to the national economy.

These two states are also the largest coal producers. Locally important black coal mining operations also include Collie in Western Australia, and Fingal and Kimbolton in Tasmania. The Gippsland Basin in Victoria contains a substantial world-class deposit where seams can be up to m thick. Minor resources occur in Tasmania's Longford Basin. Currently, brown coal is only mined in Victoria where the open-cut mines at Loy Yang and Yallourn supply coal to nearby power stations. Brown coal is also mined at Maddingley to produce soil conditioners and fertilisers.

Other products from Victorian brown coal are briquettes for industrial and domestic use and low-ash and low-sulphide char products. Open-cut mining is possible because coal seams are close to the surface. Many brown coal beds lie close to the surface and can be hundreds of metres thick, so can be extracted easily and cheaply. Firstly the topsoil is removed and stored for use later in restoring the disturbed land.

The surface rock called overburden covering the coal is then blasted with explosives and removed by excavators. The uncovered coal is in turn then blasted to break up the layers and loaded into large trucks which can hold up to tonnes of material. The coal is transported to the processing plant where impurities are removed. Coal that is deeper than a few hundred metres under the surface must be extracted using two underground mining methods.

Some coal is mined by the Bord and Pillar method. This is where a machine continually cuts into the coal. It tunnels through the coal seams leaving pillars supported by roof bolts to hold up the roof. An alternative is longwall mining, which uses a large cutting blade to slice across the coal layer to remove the coal seam. The coal is then transported to the surface on a conveyor belt.