As a result,the short hole shrinkage method with flat bottom structure was employed to mine the stope firstly,then stoping ore pillar by medium length hole caving method.

 
  • 后溝金礦采用平底結構淺孔留礦法先采礦房,后用中深孔崩落法回采礦柱,經(jīng)兩年多的生產(chǎn)實(shí)踐,取得較好的技術(shù)經(jīng)濟指標。
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