With mining downwards,it is an important problem facing Jinchuan Longshou Mine whether the upper filling body can meet require of mining the lower ore.

 
  • 隨著(zhù)開(kāi)采的不斷向下進(jìn)行,上部充填體是否能滿(mǎn)足下部開(kāi)采的需要是礦山所面臨的重要課題。
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