黔西北大坪子铅锌矿区电法组合异常特征及找矿潜力分析

Characteristics of electrical method combination and prospecting potential of the Dapingzi lead-zinc deposit in the northwestern Guizhou

大坪子铅锌矿位于垭都-蟒洞成矿带上,位于猪拱塘超大型铅锌矿的北西侧,成矿地质条件优越,碳酸盐有关的中-低温热液充填-交代型铅锌矿是本区成矿类型,矿体受地层、断裂构造和层间破碎带控制明显。为进一步研究勘查区内深部成矿条件,推断有利成矿位置,定位矿体埋藏深度,在研究勘查区铅锌矿与围岩电性条件的基础上,开展了音频大地电磁测深和激电测深综合电法测量。通过已知矿体电法组合异常特征研究认为,该区铅锌矿体一般位于音频大地电磁测深电阻率梯度变化带,激电测深低阻高极化突变位置,总体表现为明显的低阻高极化或中低阻高极化异常特征。通过总结该类型铅锌矿物探异常特征,圈定了勘查区找矿远景区,为下一步寻找硫化铅锌矿提供有利参考,提供一些找矿思路。

The Dapingzi lead-zinc deposit in the Yadu-Mangdong metallogenic belt is located in the northwest side of the Zhugongtang lead-zinc superlarge deposit.There are superior metallogenic and geological conditions in the area.The carbonate associated medium-low temperature hydrothermal filling-metasomatic lead-zinc deposit is of the metallogenic type in the area.Their orebodies are obviously controlled by strata,fractures,and interlayer fracture zones.In order to further study the ore-forming conditions in depth of the exploration area,to infer the favorable ore-forming position,to locate the buried depth of orebodies,on the basis of studying the electrical conditions of the lead-zinc ore and wallrocks in the exploration area,we have carried out the AMT and IP surveys in the area.Based on the study on the electrical method combination anomaly characteristics of known orebodies,it is believed that the lead-zinc orebodies in this area are generally located in the gradient transition zone of the AMT resistivity,the abrupt position of low resistance and high polarization by the IP.They generally show obvious characteristics of low resistance or middle-low resistance and high polarization anomalies.Through summarizing the geophysical anomaly characteristics of this type of lead-zinc ore deposit,the prospecting targets in the exploration area has been outlined.They have provided favorable references and some prospecting ideas for the next step exploration of lead-zinc sulfide ores.