- 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 ...
A suffix used in naming rocks that are porphyritic, such as vitrophyre, orthophyre, or granophyre.
Industry:Mining
A suggested type of hydrostatic support for the Earth's solid outer crust in which crustal density is supposed to be greater under mountains than under oceans. Compare: isostasy; Airy hypothesis.
Industry:Mining
A sulfate of any of various metals (such as copper, iron, or zinc,); esp. a hydrate (as the heptahydrate) of such a sulfate having a glassy appearance or luster.
Industry:Mining
A sulfate of iron and copper resulting from the decomposition of copper pyrites.
Industry:Mining
A sulfide deposit rich in copper, zinc, lead, silver, or gold, which forms as a result of hydrothermal activity in the vicinity of mid-ocean spreading centers or tectonically active basins. The first discovery of these deposits was from the French submersible Cyana, in 1979, during a joint international biological investigation of thermal springs on the deep seabed. The term derives from the French "sulfides polymetalliques."
Industry:Mining
A supplementary anode placed in a position to raise the current density on a certain area of the cathode to get better plate distribution.
Industry:Mining
A supply of compressed air at a working pressure of about 100 psi (690 kPa). The quantity required for a modern high-speed sinking may be 2,000 to 2,500 ft<sub>3</sub>/min (56.6 to 70.7 m<sub>3</sub>/min). At a new mine where two shafts are being sunk, the power installation may comprise eight slow-speed water-cooled compressors with a total output of almost 5,000 ft <sub>3</sub>/min (141.5 m<sub>3</sub>/min) at 100 psi.
Industry:Mining
A support composed of elastic materials that either yields to the roof pressure, or permits the subsidence of the roof without the support being completely destroyed and losing its significance.
Industry:Mining
A support that incorporates a sliding or flexible joint or stilt to accommodate early pressure and thus delays damage and distortion of the support. Friction or hydraulic devices may be used so that a support, when subjected to a load above its set load, yields mechanically rather than by distorting.
Industry:Mining
