thickness of overburden

См. также в других словарях:

• Overburden ratio —   Overburden ratio refers to the amount of overburden that must be removed to excavate a given quantity of coal. It is commonly expressed in cubic yards per ton of coal, but is sometimes expressed as a ratio comparing the thickness of the… …   Energy terms

• List of unusual units of measurement — For units of measure primarily used in countries where English is not the main language, see the article specific to that country, a list of which can be found in the systems of measurement article. An unusual unit of measurement is a unit of… …   Wikipedia

• Strip or stripping ratio —   The amount of overburden that must be removed to gain access to a unit amount of coal. A stripping ratio may be expressed as (1) thickness of overburden to thickness of coal, (2) volume of overburden to volume coal, (3) weight of overburden to… …   Energy terms

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• mining — /muy ning/, n. 1. the act, process, or industry of extracting ores, coal, etc., from mines. 2. the laying of explosive mines. [1250 1300; ME: undermining (walls in an attack); see MINE2, ING1] * * * I Excavation of materials from the Earth s… …   Universalium

• Coal mining — Men leaving a UK colliery at the close of a shift Surface coal mining in Wyo …   Wikipedia

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