ホーム > Term: dropping pillars and top coal
dropping pillars and top coal
(Australia) The second working, consisting of drawing the pillars, and in thick seams breaking down the upper portion of the seam that was left temporarily in position.
- スピーチの一部 noun
- 産業/ドメイン 炭鉱
- カテゴリ 炭鉱全般; Mineral mining
- Government Agency: USBM
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作成者
- ed.young
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