湖南东坡铅锌矿危机矿山找矿新进展及找矿方向

The Prospecting Progress and Direction for Exhausted Lead-zinc Ore Resource Exploration in Dongpo Ore Field,Hunan Province

湖南东坡矿田内矿产资源丰富,但已探明的铅锌资源严重危机。在综合研究该区成矿地质条件、矿床特征、成矿规律的基础上,圈出3个找矿靶区,即妹子垅、牛角垅及塘渣水预测区。根据本区矽卡岩型钨锡多金属矿、脉状铅锌矿的产状及矿石矿物组合特征,确定的勘查思路为：以已知矿床深边部为主,兼顾外围;以铅锌矿为主,兼顾钨锡多金属矿;以地质方法为主,物探方法相结合。根据本区的实际情况,选用了地面高精度磁测、激电测深、坑探、钻探等工作手段。通过物探工作,在区内圈出22个磁异常,在妹子垅发现低阻高极化体--矽卡岩型钨锡矿化体。通过工程揭露,在妹子垅预测区见到厚度10.86-32.00 m的矽卡岩型钨锡多金属矿体,矿床规模可达大型。塘渣水预测区,Ⅱ4矿体新增333＋334类Pb＋Zn资源量8.23×10^4t;500中段发现水平厚度103 m的矽卡型钨锡多金属矿体,矿床远景规模可达大型。牛角垅预测区,见到厚度大（3.58-9.37 m）、品位富（平均品位Pb 14.94%,Zn 2.22%,Ag 1 444.44×10^-6）的铅锌矿,规模达中型。通过综合研究,笔者认为东坡矿田深部及外围找矿前景好,在横山岭、蛇形坪及玉皇庙的深部,具有寻找矽卡岩型、云英岩型锡多金属矿的潜力;在沙坪里、金狮岭、古塘一带,中浅部是寻找铅锌银矿,深部是寻找矽卡岩型或蚀变岩型多金属矿的有利地段。

Although underground resources in Dongpo ore field are very abundance,the lead-zinc metal quantity is much short for further mining.Based on synthetic analysis of regional geological background,ore deposit feature and metallogenic regularity,three prospecting target are selected,which are Meizilong area,Niujiaolong area and Tangzhashui area.The ideas for prospecting have established by detailed investigation of geological characteristics of skarn-type W-Sn polymetallic and vain-type Pb-Zn ore deposits：（1） the areas nearby known ore deposit are favorable target,such as depth or rim of ore-body;（2） the favorable mine type are lead-zinc,while tungsten-tin polymetallic ore is also to be considered;（3） the geological methods is the most effective one,and geophysical method should also be useful.The high accuracy ground magnetic survey,electrical sounding,drilling or tunneling methods are used for exploration in Dongpo ore field.22 magnetic anomalies are found through geophysical operations,most exciting new is the finding of low electrical resistivity-high polarization geologic body-skarn-type W-Sn ore body in Meizilong area.The further exploration engineering proves up this skarn-type W-Sn ore body is 10.86 - 32.00 meters thick,which come to be a large scale deposit.In Tangzhashui area,the new 333＋334 class Pb＋Zn reserves of 8.23×10^4 t is added to Ⅱ4 ore body,and 103 meter thick skarn-type W-Sn polymetallic ore body are found in 500 meter level,those two new finding makes this deposit to be large scale.A large thickness（3.58 - 9.37 m） and high grade（in average： Pb 14.94%,Zn 2.22%,Ag 1 444.44 g/t） Pb-Zn ore body is found in Niujiaolong area,which maybe come to a medium scale deposit.The exploration work in Dongpo ore field illustrate that the depth and periphery of known ore deposit is the favorable prospecting target： skarn-type and greisen-type tin polymetallic ore body maybe found in depth of Hengshanling,Shexingping and Yuhuangmiao area;lead-zinc-silver ore-body may be in mid-shallow and skarn-type or altered rock-type ore-body may be in the depth of Shapingli,Jinshiling and Gutang area.