内蒙古双尖子山银多金属矿床区域地球化学特征

内蒙古双尖子山银多金属矿床是中国乃至亚洲规模最大的银多金属矿床,本研究在回顾矿床发现史的基础上对双尖子山矿床区域地球化学数据进行再分析。采用19级累积频率法制作研究区39种元素或氧化物的地球化学图,结果发现在双尖子山矿区范围内出现明显高值的有MgO、CaO、Fe₂O₃、Pb、Zn、Ag、V、Cr、Ni等多达22种氧化物或元素,其中主量成分的明显富集特征应受控于研究区的岩性分布情况。采用变值七级异常法制作研究区29种微量元素的地球化学异常图,结果发现在双尖子山矿区及其附近存在W、Sn、Mo、Bi、Pb、Zn、Ag、As、Sb计9种热液成矿元素的异常区,而其他微量元素在双尖子山矿区的明显富集情况可能是由双尖子山矿区及其附近母岩岩性及其风化作用所致。基于地球化学基因技术制作了研究区金矿化基因和钨矿化基因的矿化相似度地球化学图,结果发现在双尖子山矿区及其附近存在金矿化相似度和钨矿化相似度的异常区,表明矿化相似度可以作为该区金属矿产勘查的一种有效指标,认为区域化探工作在该区金属矿产勘查中具有很好的参考价值。

Regional Geochemical Survey in the Area of Shuangjianzishan Ag-polymetallic Deposit in Inner Mongolia,China

The Giant Shuangjianzishan Ag-polymetallic deposit in Inner Mongolia is currently the largest Ag-polymetallic deposit in China and even Asia. Based on the review of the discovery history of the deposit, the geochemical data on the regional geochemical survey are being reprocessed using new methods. A 19 levels of cumulative frequency method is used to map the analyzed 39 elements or major oxides and the results indicate that the major oxides or elements up to 22 items such as MgO, CaO, Fe₂O₃, Pb, Zn, Ag, V, Cr, Ni, etc. are enriched in the deposit area. The enrichments of major oxides may be resulted from the parent rocks in this area. The seven levels’ classification method on the geochemical anomaly with unfixed backgrounds is adopted to draw the single-element geochemical anomaly map for the 29 trace elements and the results indicate that only 9 elements such as W, Sn, Mo, Bi, Pb, Zn, Ag, As, and Sb have anomalies in or around the deposit area. Therefore, the enrichments of other trace elements in the deposit area may be caused by the parent rocks or their weathering. The recently presented method of geochemical gene is applied in this area and the mineralization similarity of metallogene is used as an integrated index to recognize the geochemical anomalies. The results indicate that the mineralization similarities of gold metallogene and tungsten metallogene all occur anomalies in or around the deposit area which reflects the ore-forming potential in the deposit area. The aforementioned results illustrate the regional geochemical survey is a useful method in the exploration of the Shuangjianzishan Ag-polymetallic deposit.