- 行业: 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 ...
A mine may be fully developed and yet, owing to the barrenness of the ore, it would be impossible to work it with profit. (Ricketts, 1943)
Industry:Mining
A mine operated to supply purchasers in general as contrasted with a captive mine.
Industry:Mining
A mine or part of a mine that is prone to outbursts and accumulations of noxious gases.
Industry:Mining
A mine power center is a combined transformer and distribution unit complete within a metal enclosure, usually of explosion-proof design, from which one or more low-voltage power circuits are taken.
Industry:Mining
A mine road having such a sharp grade that sprags are needed to control the descent of a car; hence, two-, three-, or four-sprag road.
Industry:Mining
A mine roadway along which a load is moved by a single form of haulage without coupling or uncoupling of cars and without transfer from one form of haulage to another.
Industry:Mining
A mine shaft through which ore and miners are carried, as distinguished from one used only in pumping.
Industry:Mining
A mine subsidence theory based on an extension of the theory of the normal. In it, subsidence is regarded as taking place in two stages. There is, first, a breaking of the rocks in which the lines of fracture tend to run at right angles to the stratification. This is 2155 followed by an aftersliding, or inward movement from the sides, resulting in a pull or draw beyond the edges of the workings.
Industry:Mining
A mine subsidence theory that distinguishes between the manner of fracture of shale and sandstone, holding that the former rock breaks along vertical lines irrespective of the angle of dip, and that the latter has a vertical fracture over a rise face and a fracture at right angles to the bed over a dip face. The theory predicts vertical lines of break in either rock for a level seam, and is, indeed, a compromise between the vertical theory and that of the normal.
Industry:Mining
