- 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 large timber laid flat on the ground or in a level, shallow ditch to which are fastened the drill-platform boards or planking.
Industry:Mining
A large tree-fern of the coal forest, with trunks about 2 ft (0.6 m) thick, containing several cylinders of wood inside the stem instead of one column of wood as in modern trees.
Industry:Mining
A large turntable with molds mounted on the outer edge. Used primarily in the base metal industries for cast ingots, anodes, etc.
Industry:Mining
A large wooden tub used for the final washing of valuable minerals separated by water concentration in ore dressing.
Industry:Mining
A large, basin-shaped volcanic depression, more or less circular, the diameter of which is many times greater than that of the included vent or vents, no matter what the steepness of the walls or the form of the floor may be. Compare: crater
Industry:Mining
A large, concordant, typically layered igneous intrusion, of planoconvex or lenticular shape, that is sunken in its central part owing to sagging of the underlying country rock.
Industry:Mining
A large, concordant, typically layered igneous intrusion, of planoconvex or lenticular shape, that is sunken in its central part owing to sagging of the underlying country rock.
Industry:Mining
A large, generally discordant plutonic mass that has more than 40 sq mi (104 km<sub>2</sub>) of surface exposure and no known floor. Its formation is believed by most investigators to involve magmatic processes. Also spelled: bathylith.
Industry:Mining
A large, generally discordant plutonic mass that has more than 40 sq mi (104 km<sub>2</sub>) of surface exposure and no known floor. Its formation is believed by most investigators to involve magmatic processes. Also spelled: bathylith.
Industry:Mining
