石英脉型钨矿原生晕特征及深部成矿定位预测——以赣南淘锡坑钨矿11号脉为例

Characteristics of Primary Halos for Quartz Vein-type Tungsten Deposits and its Implication in Locating Ore Bodies at Depth——A Case Study of the Taoxikeng Deposit,Southern Jiangxi Province

以往对金、银、铜、铅、锌等矿床的原生晕研究较多,而对钨矿床原生晕的研究很少。为了探求新的钨矿找矿思路,更快速有效地圈定预测靶区、进而发现隐伏矿体,本文以原生晕轴向分带理论为指导,对赣南淘锡坑钨矿11号脉6个中段内沿脉所采的样品选取W、Zn、Au、Ag、Co、Mn、As、Sb及Ce、Hf、Lu和Yb来分析钨矿原生晕的结构,建立了该矿脉的原生晕叠加模型,继而预测靶区。结果表明,Zn、Au、Ag、Co、Mn、Ce、Hf、Lu和Yb异常晕与矿体中心的距离在50m范围内,为近矿晕指示元素;As、Sb异常晕发育于钨矿体前缘,与矿体中心相距200～250m,为前缘晕指示元素;根据该矿脉原生晕模型特征,预测了56m标高的3个靶位和-144m标高的3个靶位,其中靶位1和靶位2最具找矿潜力。

Case studies on primary halos of gold, silver, copper, lead and zinc deposits are numerous, while rare on that of tungsten deposits. This study aims to sort out useful method for blind ore bodies prospecting for tungsten deposits. Guided by the theory of axial zoning of primary halos, W, Zn, Au, Ag, Co, Mn, As, Sb, Ce, Hf, Lu and Yb contents were analyzed for samples collected from six segments of vein 11 between 356 meter elevation and 106 meter elevation in the Taoxikeng Tungsten Deposit to reveal their primary halos, which was subsequently used in mineralization prognosis. The analyses show that primary halos of Zn, Au, Ag, Co, Mn, Ce, Hf, Lu and Yb are close to W ore-body, commonly within less than 50 meter, which make them central halo indicators, while those of As and Sb are frontal halo indicators occur 200 to 250 meter away from downward W ore-body. According to the comprehensive characteristics of indicators＇ primary halos pattern, the authors predicted three targets at 56 meter elevation and another three at -144 elevation in No. 11 vein, among which the No. 1 and No. 2 targets are more promising.