Coal the heat and pressure of deep burial causes the loss of water, methane and carbon dioxide and an increase in the proportion of carbon. Thus first lignite (also called "brown coal"), then sub-bituminous coal, bituminous coal, and lastly anthracite (also called "hard coal" or "black coal") may be formed. The wide, shallow seas of the Carboniferous Period provided ideal conditions for coal formation, although coal is known from most geological periods. The exception is the coal gap in the Permian–Triassic extinction event, where coal is rare. Coal is known from Precambrian strata, which predate land plants—this coal is presumed to
Coal in Europe in coal mines, caused by the liberation of methane from mining. Annual coal carbon emissions (2005–2008 average) were highest per capita in Europe in Czech Republic 7.4, Kazakhstan 6.9, Poland 5.5, Finland 4.8, Serbia 4.5 and Germany 4.1. Coal in Europe Coal production in Europe is falling, and imports exceed production. There is, however, growing controversy in Europe over the use of coal, as many denounce it for reasons such as health risks and links to global warming. International Energy Agency reports data for EU28 countries since 1990. According to IEA, EU28 countries use of coal as fuel has went