- 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 rock that exhibits planar or linear structures characteristic of metamorphic rocks, but lacks observable granulation or recrystallization, and is therefore considered to be of igneous origin.
Industry:Mining
A rock that has undergone changes in its chemical and mineralogic composition since its original formation.
Industry:Mining
A rock that macroscopically resembles phyllite but that is formed by mechanical degradation (mylonization) of initially coarser rocks (e.g., graywacke, granite, or gneiss). Silky films of recrystallized mica or chlorite, smeared out along schistosity surfaces, and formation by dislocation metamorphism are characteristic.
Industry:Mining
A rock that macroscopically resembles phyllite but that is formed by mechanical degradation (mylonization) of initially coarser rocks (e.g., graywacke, granite, or gneiss). Silky films of recrystallized mica or chlorite, smeared out along schistosity surfaces, and formation by dislocation metamorphism are characteristic.
Industry:Mining
A rock that resembles, or may easily be mistaken for, a normal sedimentary conglomerate. Examples include a crush conglomerate consisting of cemented fragments that have been rolled and rounded nearly in place by orogenic forces; a pebble dike; a sandstone packed with rounded concretions; and an aggregate of rounded boulders produced in place by spheroidal weathering and surrounded by clayey material.
Industry:Mining
A rock that was formed deep within the Earth under the influence of heat and pressure.
Industry:Mining
A rock, such as limestone, dolomite, or carbonatite, that consists chiefly of carbonate minerals; specif. a sedimentary rock composed of more than 50% by weight of carbonate minerals.
Industry:Mining
A rock, such as limestone, dolomite, or carbonatite, that consists chiefly of carbonate minerals; specif. a sedimentary rock composed of more than 50% by weight of carbonate minerals.
Industry:Mining
A rock-boring or rock-cutting tool, the cutting points of which are inset diamonds.
Industry:Mining
