东北某铅锌矿是生产能力较大的老矿山,日本及国民党统制时期,作过掠夺式的开采,使矿山遭受到严重破坏。解放后,虽然作了不少地质工作,但保有储量不多。生产部门有些人认为某些生产坑口已处于“衰老”时期,有的已经作出闭坑结论,准备撤出坑内设备。为延长矿山寿命,一九六四年四月,上级指 A lead-zinc mine in the northeast is an old mine with large production capacity. Predatory mining was conducted during the control of Japan and the Kuomintang, and the mine was severely damaged. After the liberation, although a lot of geological work done, but not much reserves. Some people in the production sector think that some of the production pit openings are already in an “aging” period, and some have concluded that they must withdraw from the pit facilities. In order to extend the life of the mine, in April 1964, the superior referred to