你要来挖掘我么?welcome啊。。。
its a valuable ore in deep covered by tonnes of overburden and it is recommended that the type of mining operation best suited to this orebody be a dragline strip mining operation with a transition into a underground long wall operaiton once the draline reaches its maximum operating overburden depth.
thats all i tell, haha...作者: 无风嗜烟 时间: 2010-6-8 21:02
顶一下
不知道怎么说感觉楼主挺有骨气 蛮有眼光的