- 行业: Mining
- Number of terms: 33118
- Number of blossaries: 0
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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 ...
Said of original rocks as opposed to derived rocks, and including saline deposits, coal, igneous rocks, and ore deposits. The term is no longer used.
Industry:Mining
Said of pyroclastic material that is characteristically glassy; i.e., contains more than 75% glass.
Industry:Mining
Said of rocks and minerals that are mechanically or chemically unstable; easily decomposed. Compare: unstable
Industry:Mining
Said of round, smooth sedimentary particles that have been rolled about by water.
Industry:Mining
Said of sedimentary rocks of different facies, or said of facies characterized by different rock types. The rocks may be formed contemporaneously or in juxtaposition in the same sedimentation area or both, but the lithologies are different; e.g., facies that replace one another laterally in deposits of the same age. Also, said of a map depicting heteropic facies or rocks. Compare: isopic
Industry:Mining
Said of sedimentary rocks of the same facies, or said of facies characterized by identical or closely similar rock types. The rocks may be formed in different sedimentation areas or at different times or both, but the lithologies are the same; e.g., a facies repeated in vertical succession. Also, said of a map depicting isopic facies or rocks. Compare: heteropic
Industry:Mining
Said of slate or other impurity that adheres tightly to coal. Similarly, coal is said to be "burned to the roof" when it is hard to separate the roof rock from the coal.
Industry:Mining
