一、地質礦床概况目前开采的南組脉分一、二兩大平行脉組,一脉組主要是10号矿脉,脉寬0.68公尺,f=6～8,矿石与圍岩均不稳固。二脉組主要是4号矿脉,脉寬0.66公尺f=7～8,傾角70～75°,体重2.7吨/立方公尺,性脆易爆,松散系数1.5,脉牆接触明显,易于分离,圍岩中粒花崗岩、云英岩化、硅化都有,平均蝕变深度0.29公尺,韧性较强于矿石,f=8～10。 4号矿脉过去絕大部分都用留矿柱或不留矿柱的标准留矿法开采,約10%的上下盤縱横节理特別发达,不稳固地 I. Overview of Geological Deposits The South Group veins currently developed are divided into one or two large parallel vein groups. One vein group is mainly No. 10 vein with a pulse width of 0.68 meters, f = 6 ~ 8, and both ore and surrounding rock are not stable. The second vein is mainly No. 4 vein, pulse width 0.66 meters f = 7 ~ 8, dip 70 ~ 75 °, body weight 2.7 tons / cubic meter, sexual brittle explosive, loose coefficient 1.5, pulse wall contact obvious, easy to separate The granite, dolostone and silicification of the surrounding rocks all have the average alteration depth of 0.29 meters and the toughness is stronger than that of the ore, f = 8 ~ 10. In the past, most of the 4 ore veins were mined by the standard ore retention method with or without the ore column. About 10% of the vertical and horizontal joints of the upper and lower plates were particularly well-developed and unstable