Petroleum and natural gas are found in the Earth's subsurface with the tools of petroleum geology and are a significant source of fuel and raw materials for the production of organic chemicals. The extraction of liquid hydrocarbon fuel from sedimentary basins is integral to modern energy development. Hydrocarbons are mined from tar sands and oil shale, and potentially extracted from sedimentary methane hydrates. These reserves require distillation and upgrading to produce synthetic crude and petroleum. Hydrocarbons are economically important because major fossil fuels such as coal, petroleum and natural gas, and its derivatives such as plastics, paraffin, waxes, solvents and oils are hydrocarbons. Kit contains:. Cap rock: mudstone. Reservoir rock (limestone). Reservoir rock (limestone): oolitic. Cap rock A: shale. Lignite sample. Anthracite coal. Bituminous coal. Source Rock (oil shale Kimmeridge). Reservoir rock (sandstone). Cap rock B: gypsum. Peat sample. Oil tar sand, crude oil.