安徽西湾铅锌矿含矿层位顶部原生晕特征

Primary halo characteristics on the top of the ore-bearing horizon in the Xiwan lead-zinc deposit in Anhui Province

安徽西湾铅锌矿位于庐枞火山岩盆地北缘,该区属于第四系覆盖区,勘查难度大。本文利用钻孔岩心样的分析结果,对西湾铅锌矿的原生晕特征进行研究,发现矿化带及其顶、底板的元素含量及异常特征差异明显:矿化带赋存的角砾状灰岩中Pb、Zn、Ag、As、Sb、Bi、Au、Cu、Mo等含量高,异常强度及规模大,具清晰的浓度和组分分带,异常不仅很好地反映了矿体特征,对矿体呈NE向延伸的趋势指示明显;而矿化带顶板的火山岩中As、Sb、Pb、Zn、Ag等含量较高,有较弱的异常,异常无明显的分带特征,仅对采样点附近矿体有一定的指示;底板的硬石膏上述元素含量低,无明显的异常显示。本区As、Sb、Pb、Zn、Ag、Mo为铅锌矿化的指示元素。采集于不同成矿部位的岩心样的元素含量及其异常特征,可以指导矿区的进一步找矿。

The Xiwan lead-zinc deposit in Anhui Province is located on the northern margin of the Luzong volcanic basin.This deposit is an overburden area,causing great difficulties with exploration.Based on the analysis results of borehole core samples,this study analyzed the characteristics of the primary halos of the Xiwan lead-zinc deposit.The results show that the mineralized zone and its roof and floor have significantly different contents and anomaly characteristics of elements.Specifically,brecciated limestones in the mineralized zone have high contents of elements such as Pb,Zn,Ag,As,Sb,Bi,Au,Cu,and Mo.These elements feature high anomaly intensity and large anomaly scales and have definite concentrations and component zoning.These element anomalies effectively reflect the characteristics of orebodies and significantly indicate the NE-trending extension of ore bodies.The volcanic rocks on the roof of the mineralized zone have high contents of elements such as As,Sb,Pb,Zn,and Ag.These elements feature weak anomalies without significant zoning.These element anomalies can only indicate the ore bodies near the sampling points.The anhydrites on the floor have low contents of the abovementioned elements,without significant anomaly.Therefore,As,Sb,Pb,Zn,Ag,and Mo are indicator elements of lead-zinc mineralization in the study area.The brecciated limestones in the mineralized zone have high element contents,forming anomalies with high intensity and large scales.Moreover,these anomalies are characterized by significant concentrations and component zoning and can clearly indicate the extension direction of ore bodies.The contents and anomaly characteristics of elements in the core samples collected from different metallogenic parts can guide the further prospecting of the mining area.