- 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 timber staging on the floor of a stope for setting a rock drill. The stage is tilted to enable the bottom holes being drilled in the same inclined direction.
Industry:Mining
A timber that in an emergency can be dropped by a remote control across a mine track at the top or bottom of an incline to derail cars.
Industry:Mining
A timber, or timber and steel structure, to provide support at the ripping lip. There are various types: one consists of bent corrugated steel bars behind which wooden planks are wedged; another consists of adjustable stretchers that are fitted across the roadway.
Industry:Mining
A timber, steel, concrete, or other erection in a roadway to (1) ensure safety by preventing falls of ground, and (2) maintain the maximum possible roadway size by 2664 resisting the tendency of the roadway to contract and distort.
Industry:Mining
A time marked on a record to correspond to some arbitrary time. Such marks may aid in synchronizing different records or may indicate a reference, such as a datum plane.
Industry:Mining
A time of deformation, typically recorded in the eastern Rocky Mountains of the United States, whose several phases extended from late Cretaceous until the end of the Paleocene. It is named for the Laramie Formation of Wyoming and Colorado, probably a synorogenic deposit.
Industry:Mining
A time-weighted average concentration under which most people can work consistently for 8 hours a day, day after day, with no harmful effects. A table of these values and accompanying precautions is published annually by the American Conference of Governmental Hygienists.
Industry:Mining
A tiny, spherical, incipient crystal visible in some volcanic glasses examined in thin section under a polarized-light microscope.
Industry:Mining
