Term
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Definition
| the federal coal mine health and safety act of 1969 |
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Term
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Definition
| a nearly horizontal passage from the surface by which a mine is entered and dewatered. a blind horizontal opening into a mountain with only one entrance |
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Term
| British Thermal Unit (BTU) |
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Definition
| the quantity of heat required to raise the temperature of one pound of distilled water one degree F at its maximum point of density |
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Term
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Definition
| exploitation in the same direction, or order of sequence, as development is known as mining in advance |
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Term
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Definition
| any passage through which air is carried (also known as aircourse) |
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Term
| Alluvial Deposit / Placer Deposit |
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Definition
| Earth, sand, gravel, or other rock or materials transported by and laid down by flowing water. Alluvial deposits generally take the form of (1)surface deposits, (2)river deposits, (3)deep leads, and (4)shore deposits. |
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Term
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Definition
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Term
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Definition
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Term
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Definition
| coals with a volatile-carbon ratio equal to .12 or less |
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Term
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Definition
| a water bearing bed of porous rock, often sandstone |
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Term
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Definition
| A rotary drill for soft materials that uses a screw device to penetrate, break, and then transport the drilled material. Auger type devices are often popular in soft coal. To aid in penetration and decrease wear on the auger rods, a hard faced bit is used at the contact between drill and fresh material. |
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Term
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Definition
| all activities supportive of but not contributing directly to the winning of coal, ore, or stone |
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Term
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Definition
| the roof or upper part in any underground mining cavity |
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Term
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Definition
| said of rock or vein material containing no minerals of value, and of strata without coal, or containing coal in seams too thin to be workable |
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Term
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Definition
| a plate used to distribute a given load, in roof bolting, the plate used between the bolt head and the roof |
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Term
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Definition
| a stratum of coal or other sedimentary deposit. the smallest division of a stratified series, marked by a more or less well defined divisional plane from its neighbors above and below. |
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Term
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Definition
| the solid rock of earths crust |
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Term
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Definition
| to improve the grade by removing gangue material; to upgrade |
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Term
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Definition
| the treatment of mined material, making it more concentrated or richer. synonyms: processing, preparation,dressing, cleaning |
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Term
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Definition
| a term generally applied to carbon dioxide. strictly speaking it is a mixture of carbon dioxide and nitrogen. it is also applied to an atmosphere depleted of oxygen, rather than having an excess of carbon dioxide. |
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Term
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Definition
| a controlled explosion which is used to loosen the substance being mined |
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Term
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Definition
| any deep or long drill hole, usually associated with a diamond drill or an oil-well drill |
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Term
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Definition
| floor or underlying surface of an underground excavation |
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Term
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Definition
| any member of the managerial ranks who is directly in charge of miners. higher ranking personnel are called foreman, superintendents, managers, etc. |
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Term
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Definition
| a passage for ventilation which is cut through the pillars between rooms |
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Term
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Definition
| a rubber-tire mounted mobile conveyor, about 10 meters long, used as an intermediate unit to create a system of articulated conveyors between a mining machine and a room or entry conveyor |
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Term
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Definition
| a short conveyor hung from the boom of a mining or loading machine or haulage system with the other end attached to a recieving bin that dollies along a frame supported by the room or entry conveyor tailpeice. thus as the machine bin moves the bridge conveyor keeps it in constant connection with the tailpeice. |
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Term
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Definition
| a low place in the ceiling of a mine, giving insufficient headroom |
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Term
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Definition
| a short, poorly defined vertical cleavage plane in a coal seam, usually at right angles to the long face cleat |
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Term
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Definition
| the quantity of heat that can be liberated from one pound of coal or oil measure in BTU's |
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Term
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Definition
| a protective covering of a cab on a mining machine |
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Term
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Definition
| more correctly, cemented tungsten carbide. a cutting or drilling bit for rock or coal, made by fusing an insert of molded tungsten carbide to the cutting edge of a steel bit shank |
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Term
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Definition
| a collapse of the mine workings |
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Term
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Definition
| describes a person who has passed an examination to do a required job |
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Term
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Definition
| the pillar of coal left to protect the gangway or entry and the parallel airways |
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Term
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Definition
| large hydraulic jacks used to support the roof in longwall and shortwall mining systems (see crib) |
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Term
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Definition
| a body of clay-like material that fills a void in a coal bed |
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Term
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Definition
| the vertical cleavage of coal seams. the main set of joints along which coal breaks when mined |
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Term
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Definition
| a solid, brittle, more or less distinctly stratified combustible carbonaceous rock, formed by partial to complete decomposition of vegetation; varies in color from dark brown to black; not fusible without decomposition and very insoluble |
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Term
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Definition
| Particles of dust that can pass through a No. 20 sieve |
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Term
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Definition
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Term
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Definition
| measured tonnages of coal that have been calculated to occur in a coal seal within a particular property |
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Term
| Code of Federal Regulations, Title 30 |
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Definition
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Term
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Definition
| the term applied to the timbering or concrete around the mouth or top of a shaft. the beginning point of a shaft or drill hole, the surface (see crossbar) |
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Term
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Definition
| British name for coal mine |
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Term
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Definition
| the breaking, crushing, or grinding of coal, ore, or rock |
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Term
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Definition
| rock which, because of its physical and geological characteristics, is capable of sustaining openings without any structural support except pillars and walls left during mining (stulls, light props, and roof bolts are not considered structural support |
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Term
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Definition
| a machine that constantly extracts ore (usually, but not always, coal) while it loads it. this is to be distinguished from a conventional, or cyclic, unit, which must stop the extraction process in order for loading to commence. |
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Term
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Definition
| any coal mining process that frees the coal from the face mechanically and loads continuously, thus eliminating the cycles of cutting drilling and shooting |
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Term
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Definition
| an apparatus for moving material from one point to another in a continuous fashion. this is accomplished with an endless (that is, looped) procession of hooks, buckets, wide rubber belt, etc. |
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Term
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Definition
| the valueless rock surrounding a lode |
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Term
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Definition
| the overburden of any deposit |
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Term
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Definition
| a roof support of prop timbers or ties, laid in alternate cross-layers, log-cabin style. it may or may not be filled with debris. also called a chock or cog. |
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Term
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Definition
| coal at the outcrop of the seam. it is usually consideredof inferior quality due to partial oxidation although this is not always the case. |
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Term
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Definition
| a passageway driven between the entry and its parallel aircourse or air courses for ventilation purposes. Also, a tunnel driven from one seam to another through or across the intervening measures; sometimes called "crosscut tunnel" or "breakthrough". In vein ming, an entry perpendicular to the vein. |
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Term
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Definition
| unconcentrated ore as it leaves the mine |
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Term
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Definition
| a machine for crushing rock or other materials. Among the various types of crushers are the ball mill, gyratory crusher, Hadsel mill, hammer mill, jaw crusher, rod mill, rolls, stamp mill, and tube mill. |
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Term
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Definition
| minimum grade of mineral in an ore that can be mined profitably. |
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Term
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Definition
| the pattern in which multiple gaces are advanced when driving entries or rooms |
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Term
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Definition
| a machine, usually used for coal, that will cut a 10-15 cm slot. The slot allows room for expansion of the broken coal. Also applies to the man who ooperates the machine, and to workers engaged in the cutting of coal by pick or drill. |
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Term
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Definition
| mineral deposit or ore deposit is used to designate a natural occurrence of a useful mineral, or an ore, in sufficient extent and degree of concentration to invite exploitation |
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Term
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Definition
| work don on a mine after exploration to provide access to the ore and to provide haulageways for the exploitation period. Alt: the work of driving openings to and in a proved ore body to prepare it for mineing and transporting the ore or other material. These operations include tunneling, sinking, cross-cutting, drifting, and raising. |
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Term
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Definition
| work undertaken to open up ore bodies as distinguished from exploratory work on the one hand and from stope preparation on the other. |
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Term
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Definition
| a discordant tabular body of igneous rock that was injected into a fisure when molten, that cuts across the structure of the adjacent country rock, and which usually has a high angle of dip. It should not be confused with a vein. |
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Term
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Definition
| the comtamination of ore with barren wall rock in stoping. |
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Term
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Definition
| any work injury which does not result in death but which either results in any permanent impairment to the injured person or causes the injured person to lone one full day or more from work after the day of injury. |
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Term
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Definition
| process of removing surplus ground or surface water either by artificial means or by gravity flow. |
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Term
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Definition
| soft slate, shale, or rock from approximately 1 cm to 10 cm thick and located immediately above certain coal seams , which falls qquite easily when the coal support is withdrawn. |
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Term
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Definition
| a horizontal passage underground. A drift follows the vein, as distinguished from a crosscut which intersects it, or a level or gallery, which may do either; in coal mining, an entry above water level and generally on the slope of a hill, driven horizontally into a coal seam. |
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Term
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Definition
| a machine utilizing rotation, percussion (hammering), or a combination of both to make holes. If the hole is much ove 0.4 in diameter, the machine is called a borer. |
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Term
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Definition
| use of a machine to create holes for exploration or for loading with explosives. |
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Term
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Definition
| excavate horizontally, or at an inclination, as in a drift, adit, or entry. Distinguished from sinking and raising. |
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Term
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Definition
| to unload; specifically, a load of ore coal or waste; the mechanism for unloading, eg. a car dump (sometimes called triple); or the pile created by such unloading, eg. a waste dump (also called heap, pile, tip, spoil pile, etc.) |
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Term
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Definition
| multiplier by which the concentration of an element must be increased to become commercially minable. |
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Term
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Definition
| an underground horizontal or near-horizontal passage used for haulage, ventilation, or as a manway; a cola heading; a working place where coal is extracted from the seam in the initial mining; same as "gate" and "roadway", both British terms |
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Term
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Definition
| the work involved in gaining knowledge of the size, shape, position and value of an ore body. |
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Term
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Definition
| the process of economic recovery or removal of the developed mineral body |
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Term
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Definition
| any rapidly combustive or expanding substance. The energy released during this rapid combustion or expansion can be used to break rock. |
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Term
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Definition
| process of mining and removal of coal or ore from a mine |
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Term
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Definition
| the principal operating place in a mine. The working place where fresh ore or coal is exposed and extracted. A mine may have many operating faces. |
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Term
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Definition
| The principal cleavage plane or joint at right angles to the stratification of the coal seam. |
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Term
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Definition
| any conveyer used parallel to a working face with deliver coal into another conveyor or into a car. |
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Term
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Definition
| ratio of the ultimate breaking strength of the the material to the force exerted against it. If a rope with break under a load of 2721 kg (6000 lb), and it is carrying a load of 907 kg (2000 lb), its factor of safety is 2721 divided by 907 (6000 divided by 2000) which equals 3. |
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Term
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Definition
| a mass of roof rock or coal which has fallen in any part of a mine. |
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Term
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Definition
| any work injury resulting in death, regardless of the time intervening between injury and death. |
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Term
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Definition
| a slip surface between two portions of the earth's surface that have moved relative to each other. A fault is a failure surface and is evidence of severe earth stresses. |
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Term
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Definition
| a machine that meters coal onto a conveyor belt evenly and reduces oversized materials. |
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Term
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Definition
| any material that is put back in place of the extracted ore to provide ground support. |
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Term
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Definition
| the combustible gas, methane, CH4. Also, the explosive methane-air mixtures with between 5% and 15% methane. A combustible gas formed in mines by decomposition of coal or other carbonaceous matter, and that consists chiefly of methane. |
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Term
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Definition
| emergency care of a person who is ill or injured to prevent death or further injury, relieve pain, and counteract shock until medical aid is obtained. |
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Term
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Definition
| said of deposits and coal seams with a dip up to 0.08 rad (5 degrees). |
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Term
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Definition
| fine coal-dust particles carried in suspension by air currents and eventually deposited in return entries. Dust consisting of particles of coal that can pass through a No. 200 sieve. |
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Term
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Definition
| the part of any underground working upon which a person walks or upon which haulage equipment travels; simply the bottom or underlying surface of an underground excavation |
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Term
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Definition
| the wall or rock uner a vein. It is called the floor in bedded deposits. |
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Term
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Definition
| as defined and used by the US Geologival Survey (USGS), the ordinary unit of geologic mapping consisting of a large and persistent stratum of some one kind of rock. Also, it is loosely employed for any local and more or less related group of rocks. |
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Term
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Definition
| remains, impression, or trace of an animal or plant of past geologic ages preserved in the earth's crust. |
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Term
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Definition
| easy to break, or crumbling naturally. Dexcriptive of certain rocks and minerals. |
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Term
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Definition
| a horizontal or a nearly horizontal underground passage, either natural or artificial |
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Term
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Definition
| the mineral material in an ore, forming part of a vein, reef or lode, that is not commercially useful. Gangue minerals are discarded as tailings as soon as they can be separated from the useful or valuable minerals, during the concentration process. |
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Term
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Definition
| one who studies the constitution, structure, and history of the earth's crust, conducting research into the formation and dessolution of rock layers, analyzing fossil and mineral content of layers, and endeavoring to fix historical sequence of development by relating characteristics to known geological influences (historical geology).. |
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Term
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Definition
| a science that deals with the history of the earth and its life, expecially as recorded in the rocks. The principal branches are: (1) structural, or geotectonic, geology, dealing with the form, arrangement, and interal structure of the rocks; (2) dynamic geology, dealing with the causes and processes of geological change; (3) historical geology, aiming to give a chronological account of events in the earth's history; (4) economic geology, which deals with the applications of the science in industrial relations and operations; (5) mining geology, a subdivision of economic geology concerned with the application of geologic facts and principles to mining; and (6) stratigraphic geology, a study of the succession of the beds of rock laid down during the process of geologic ages. |
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Term
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Definition
| one who studies sesmic, gravitational, electrical, thermal, and magnetic phenomena to determine structure and composition of the earth, and forces causing movement and warping of surface. Investigates origin and activity of glaciers and volcanoes, and the course and phenomena of earthquakes; charts ocean currents and tides; takes measuremtns concerning shape and movements of the earth, and acoustic, optical and electrical phenomena in the atmosphere; and locates petroleum and mineral depositis. May specialize in a particular phase of the work, as exploration, administration, research, consulting, design, or teaching. |
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Term
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Definition
| the science of the earth with respect to its structure, composition, and development. It is branch of experimental physics delaing with the earth, including its atmosphere and hydrosphere. It includes the science of dynamical geology and physical geography, and makes use of geodesy, geology, seismology, meteorology, oceanography, magnetism, and other earth sciences in collecting and interpreting earth data. Geophysical methods have been applied successfullly to the identification of underground structures in the earth and to the search for structures of a particular type, as for example, those associated with oil-bearing sands. |
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Term
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Definition
| the term applied to that part of the mine from which the coal has been removed and the space more or less filled up with waste. Also, the loose waste in a mine. Also called goaf. |
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Term
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Definition
| the proportion of metal contained in unit weight of ore, even though the metal is in the form of a mineral. The grade is usually expressed as a percentage by weight. For instance, a grade of 4% lead means that a ton of lead ore contains 80 lb of lead, usually in the form of the mineral galena (lead sulphide, PbS). Same as "tenor". |
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Term
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Definition
| the arresting of the closure of the walls of a mined area. |
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Term
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Definition
| the wall or rock on the upper side of an inclined vein. It is called the roof in bedded deposits. |
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Term
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Definition
| loosely used to distinguish igneous and metamorphic from sedimentary rock. |
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Term
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Definition
| the horizontal transport of ore, coal, supplies, and waste. The vertical transport of the same is called hoisting. |
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Term
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Definition
| applied to the rising of the bottom after removal of the coal. a sharp rise in the floor is called a "hogsback". |
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Term
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Definition
| a sharp rise in the floor of a seam. |
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Term
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Definition
| the vertical transport of broken ore or material |
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Term
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Definition
| made up of similar parts of elements; of the same composition or structure throughout; uniform. Opposite of heterogeneous. |
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Term
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Definition
| in geology, any given definite position or interval in the stratigraphic column or the scheme of stratigraphic classification; generally used in a relative sense. |
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Term
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Definition
| a mass of material with a slippery surface in the roof; shaped like a horse's back |
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Term
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Definition
| mining by washing sand and dirt away with water whick leaves the desired mineral. In underground hydraulic mining, the extraction of coal by high-velocity water jets, directed at the seam from a monitor or powerful jet, which can withstand high water pressures. The jets are also used to impel the broken coal along the floor to the point of collection. |
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Term
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Definition
| in the direction of the working face |
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Term
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Definition
| any entry to a mine that is not vertical (shaft) or horizontal (adit). Often incline is reserved for those entries that are too steep for a belt conveyor (+17 degrees - 18 degrees), in which case a hoist and guide rails are employed. A belt conveyor incline is termed a slope. Alt: secondary inclined opening, driven upward to connect levels, sometimes on the dip of a deposit also called "inclined shaft". |
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Term
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Definition
| applied to strata, a formation, a rock, or a rock structure not combining sufficient firmness and flexibility to transmit a thrust and to lift a load by bending. |
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Term
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Definition
| ore for which quanitiativ estimates are based largely on broad knowledge of the geologic character of the deposit and for which there are few, if any, samples or measurements. The estimates are based on an assumed continuity or repetition for which there is geologic evidence; thisevidence may include comparison with deposits of similar type. Bodies that are completely concealed may be included if ther is specific geologic evidence of their presence. Extimates of inferred ore shouold include a statement of the special limits within which the inferred ore may lie. |
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Term
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Definition
| in the natural or original position. Applied to a rock, soil, or fossil when occurring in the situation in which it was originally formed or deposited. |
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Term
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Definition
| the passage through which fresh air is drawn or forced into a mine or to a section of a mine. |
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Term
| Job Safety Analysis (JSA) |
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Definition
| a job breakdown that give a safe, efficient job procedure. |
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Term
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Definition
| Ky Department of Mines and Minerals, the state mining regulatory agency. It is comprised of the following divisions: The Oil and Gas Division, The Explosives and Blasting Division, The Miner Training, Education, and Certification Division, and The Mine Safety Analysis Division. |
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Term
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Definition
| a smooth, rounded piece of rock, cylindrical in shape, which may drop out of the roof of a mine without warning. The origin of this feature is thought to be the remains of the stump of a tree which has been replaced by sediments so that the original form has been rather well preserved. |
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Term
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Definition
| the undercut of a coal face |
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Term
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Definition
| the electric cap lamp worn for visibility. Also the flame safety lamp used in coal mines to detect methane gas concentrations and oxygen deficiency. |
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Term
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Definition
| the design or patter of the main roadways and workings. The proper layout of mine workings is the responsibility of the manager aided by the planning department. |
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Term
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Definition
| of ore, low-grade; submarginal; unpay; of doubtful exploitable value. |
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Term
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Definition
| a brownish-black coal in which the vegetal (vegetable) material has been altered more than in the case of peat but not as much in sub-bituminous coal. |
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Term
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Definition
| the character of a rock described in terms of its structure, color, mineral composition, grain size, and arrangement of its component parts; all those visible features that in the aggregate impart individuality of the rock. Lithology is the basis of correlation in coal mines and commmonly is reliable over a distance of a few miles. |
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Term
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Definition
| to place explosives in a drill hole. also, to transfer broken material into a haulage divice; also caled "mucking" |
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Term
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Definition
| any divice for transferring broken or blasted ore or coal rock into the haulage equipment |
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Term
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Definition
| strictly, a fissure in the country rock filled with mineral; usually applied to metallifeous lodes. In general miners' usage, a lode, vein, or ledge is a tabular deposit of valuable mineral between definite boundaries. Whether it is a fissure formation or not is not always known, and does not affect the legal title under the US federal and local statutes and customs relative to lodes. As used by miners before being defined by any authority, the term lode simply means that formation by which the miner couold be led or guided. It is an alteration of the verb lead; and whatever the miner could follow, expecting to find ore, was his lode. Some formation within which he could find ore, and out of which he could not expect to find ore, was his lode. Lode, as used by miners, is nearly synonymous with the term vein, as employed by geologist. The word should not be used for a flat or stratified mass. |
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Term
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Definition
| a system of mining coal in which all of the coal or other tabular deposit is removed except the shaft pillars and sometimes the main-road pillars; characterized by its breadth (600-1000') and by its continuous nature |
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Term
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Definition
| coal fragments larger in size that coal dust |
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Term
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Definition
| mine safety and health administration |
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Term
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Definition
| main haulage road. where the coal has cleats, main entries are driven at right angles to the face cleats. |
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Term
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Definition
| a carrier of personal, by rail or rubber tire, to and from the work area. |
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Term
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Definition
| ore for which tonnage is computed from dimensions reveled in outcrops, trenches, workings, and drill holes and for which the grade is computed from the results of detailed sampling. The sites for inspection, sampling, and measurement are so closely spaced and the geologic character is so well defined that the size, shape, and mineral content are well established. The computed tonnage and grade are judged to be accurate within limits which are stated, and no such limit is judged to differ from the computed tonnage or grade by more than 20%. |
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Term
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Definition
| the most common explosive gas found in coal mines; it is tasteless, colorless, odorless, and nontoxic. Methane mixtures are called firedamp. |
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Term
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Definition
| the practice of removing the gas contained in a coal seam and adjoining strata through wellbores, drillholes, and pipelines. Also called "coal degasification". |
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Term
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Definition
| an electronic instrument often mounted on a piece of mining equipment, that detects and measure the methane content of mine air |
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Term
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Definition
| an economically viable plant for the extraction of minerals from the earth. A mine includes all the equipment, structures, and buildings involved in this process. Alt: an excavation made in the earth to extract minerals and other materials. |
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Term
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Definition
| all the physical facilities provided to operate a mine |
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Term
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Definition
| the layer of hardened clay, limestone, sandstone, or other material that lies over the coalbed; rock or other material abouve the coal seam. |
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Term
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Definition
| one who is engaged in the business or occupation of extracting ore, coal, precious substances, or other matural materials from the earth's crust. |
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Term
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Definition
| an inorganic compound occurring naturally in the earth's crust with a distinctive set of physical properties, and definite chemical composition. Minerals may be described as: (1) common, or (2) commercially useful. |
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Term
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Definition
| term covers a wide field in which many resources of modern science and engineering are used in discovery, development, exploitation, and use of natural mineral deposits. Alt: the art and science applied to the processes of mining and the operation of mines. |
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Term
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Definition
| a small form of gas mask for protection against carbon monoxide. It is a small canister with a mouthpiece directly attached to it. Teh wearer breathes through the mouth, the nose being closed by a clip. The canister contains a layer of fused calcium chloride to absorb the water vapor in the air which destroys the efficiency of the CO-absorbing chemical called hopcalite. The self-rescuer affords protection for 30 min, so that miners surviving an explosion may walk out through a mine atmosphere that contains sufficient oxygen but also a fatal concentration of carbon monoxide. |
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Term
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Definition
| any extractive process for the economic removal of minerals from the earth. Mining is a materials-handling industry with the special function of transporting minerals from their natural place to a treatment plant. Alt: the process of obtaining materials of economic value from the earth's crust for the benefit of mankind. |
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Term
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Definition
| a person qualified by education, training, and experience in mining engineering. A trained engineer with knowledge of the science, economics, and arts of mineral location, extraction, concentration and sale, and the administrative and financial problems of practical importance in connection with the profitable conduct of mining. Usually he/she is a specialist in one or more branches of his work. Activities may incllude prospecting, surveying, sampling and valuation, technical underground management, milling, assaying, ventilation control, layout of working and plant, geological examination, and company administration. |
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Term
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Definition
| the branch of engineering chiefly concerned with the discovery, development, and exploitation of coal, ores, and minerals. |
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Term
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Definition
| arbitrary quantitative units by means of which the scratch hardness of a mineral is determined. The units of hardness are expressed in numbers ranging from 1 through 10, eqach of which is represented by a mineral that can be made to scratch any other mineral having a lower-ranking number; hence the minerals are ranked from the softest to hardest, as follows: talc (1) gypsum (2), calcite (3), fluorite (4), apatite (5), orthoclase (6), quartz (7), topaz (8), corundum (9), diamond (10). |
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Term
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Definition
| a small mass of metal, such as gold or silver found free in nature. The term is restricted to pieces of some size, not mere "colors" or minute particles. Fragments and lumps of vein gold are not called nuggets for the idea of alluvial origin is implicit. |
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Term
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Definition
| any abnormal condition or disorder, other than one resulting from an occupational injury, caused by exposure to environmental factors associated with employment. It includes acute and cronic illnesses or diseases which may be caused by inhalation, absorption, ingestion, or direct contact. |
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