- Industry: Mining
- Number of terms: 33118
- Number of blossaries: 0
- Company Profile:
The U.S. Bureau of Mines (USBM) was the primary United States Government agency conducting scientific research and disseminating information on the extraction, processing, use, and conservation of mineral resources.
Founded on May 16, 1910, through the Organic Act (Public Law 179), USBM's missions ...
Applied to a method of blasting on a face not exceeding 30 ft or 35 ft (9.1 m or 10.7 m) in height. It involves leaving at the quarry face a mass of shattered rock several feet in 329 thickness that serves as a buffer, preventing the rock from being thrown far from its source, and also rendering the shot more effective.
Industry:Mining
Applied to a method of working by single panels. Single 100-yd (91-m) panels are advanced, leaving 100-yd-wide coal pillars between them. The pillars are then worked on the retreat after the advancing faces have reached a limit line.
Industry:Mining
Applied to a mine or part of a mine that generates methane in considerable quantities.
Industry:Mining
Applied to a mineral that sparks when struck with steel or iron; e.g., pyrite.
Industry:Mining
Applied to a series of small bumps or cracking noises within the walls. Bumping, talking, and spitting are signs that the rock is beginning to yield to the stresses and indicate a change in conditions within the rock.
Industry:Mining
Applied to a texture characteristic of diabases or dolerite in which euhedral or subhedral crystals of plagioclase are embedded in a mesotasis of pyroxene crystals, usually augite. Also said of a rock with such a texture. Compare: poikilitic
Industry:Mining
Applied to a texture of metamorphic rocks in which the constituent mineral grains lack proper crystal faces.
Industry:Mining
Applied to air moving through the fan that never reaches the working faces. It leaks through poor stoppings, around doors and so on, back into the returns without moving anywhere near the active sections. Surveys of some mines show that up to 80% of the air moving through the fan never reaches the working faces.
Industry:Mining
Applied to all equipment that is self-propelled or that can be towed on its own wheels, tracks, or skids.See also: transportable equipment
Industry:Mining
