河南老里湾银铅锌矿床原生晕分带特征及深部矿体预测

老里湾银铅锌矿床是近年来在河南崤山断裂东部地区新发现的一处大型矿床,矿体呈囊状、似层状、透镜状等不规则形态产出,主要受北西向F1断裂构造蚀变带及次级断裂控制。为了探讨矿体向深部延伸情况和盲矿体位置,文章选取F1断层内A-A’剖面上的4个钻孔岩心进行原生晕分带特征研究,运用格里戈良分带指数法和数理统计法对F1-1矿体的原生晕特征进行了详细的研究。发现该矿体的原生晕分带明显,前缘元素为As、Sb、Hg,近矿晕元素为Au、Ag、Cu、Pb、Zn,尾晕元素为W、Sn、Bi、Cr、Ni;轴(垂)向分带序列为:W-Sn-Cd-Ni-Sb-Cu-Ag-Au-Hg-Zn-As-Pb,出现了W、Sn、Cd、Ni等尾晕元素在上部和Hg、As等前缘晕元素及Zn、Pb等近矿晕元素在下部的"反向分带"现象,结合成矿元素和前缘晕元素在矿体下部异常值较高,推断深部存在隐伏矿体。并建立了深部矿体预测模型,初步认为矿床深部的西北侧存在着斑岩型铜(金)-钼(钨、锡)盲矿体。

Primary halo characteristics and prediction of deep ore body in the Laoliwan Ag-Pb-Zn deposit, Henan Province

Laoliwan Ag-Pb-Zn Deposit is a newly discovered large deposit,which is lies in Eastern of Xiaoshan Mountain fracture. The ore body is irregular shape output as a cystic,layered,lenticular. It is mainly controlled by the F1 faults of the NW alteration zone and subsidiary fracture. In order to explore the depth extension of ore body and the location of blind ore body,four drilling cores sample in A-A’ section of F1 fault are studied on the characteristics of primary halos in this paper. Using the way of the Grigorian zonation index and mathematical statistics,the primary halo characteristics of F1-1 orebody were studied in great detailed. The primary halo zonation of the ore body is obvious,the results shows front element is As,Sb and Hg;tail element is Au,Ag,Cu,Pb and Zn;proximal element is W,Sn,Cd and Ni;vertical zoning sequence W-Sn-Cd-Ni-Sb-Cu-Ag-Au-Hg-Zn-As-Pb,with reverse zoning phenomenon of W,Sn Cd,Ni,and Hg,As. Combine the abnormal value of the ore-forming element and front element is higher in the lower part of the ore body,it is inferred that there is concealed ore in the deep part. The prediction model of deep ore body is established,and initially consider that the porphyry Cu( Au)-Mo( W,Sn) ore body was found on the northwest side of the deep part of the deposit.