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东窝东铜多金属矿床位于羌塘地体南缘,班公湖-怒江成矿带西段,多龙铜金矿集区东侧,是新发现的重要找矿前景区。为进一步确定矿区成矿地质条件及找矿潜力,通过对矿区详细的地质调查和钻孔编录,运用离子探针(SHRIMP)对含矿斑岩进行锆石年代学研究,并利用等离子质谱仪(ICP-MS)对其进行地球化学和SrNd-Pb同位素分析。结果显示,东窝东矿区含矿斑岩结晶时代为122 Ma,是区域早白垩世成矿事件的产物,Sr-NdPb同位素组成(Sr初始值为0.7052~0.7062,143 Nd/144 Nd比值为0.512365~0.512409,εNd(t)值为-4.05~-3.88;~(206)Pb/~(204)Pb、~(207)Pb/~(204)Pb、~(208)Pb/~(204)Pb分别为18.691~18.823、15.638~115.796、38.649~38.924,揭示含矿斑岩岩浆源区有明显的壳幔混合,可能为来源于班怒洋俯冲环境下的新生下地壳。为科学判定矿区成矿潜力,解决矿区找矿瓶颈问题,综合分析矿区地质、物探(1/1万磁法和激电中梯测量)和化探(1/1万水系沉积物测量)成果后认为,东窝东矿区有良好的成矿地质条件,物、化探异常分布集中,叠合较好,存在重要找矿潜力,建议以斑岩-浅成低温热液型铜多金属矿床为勘查找矿方向。
The Dongwo Dong copper polymetallic deposit is located in the southern margin of the Qiangtang terrane, the west part of the Bangong Lake-Nujiang metallogenic belt and the east of the Duolong copper-gold ore area, which is a newly discovered important prospecting prospect area. In order to further determine the ore-forming geological conditions and the prospecting potential, the zircon geochronology of the porphyry-bearing porphyry was studied by using the SHRIMP (geophysical prospecting) ICP-MS) for its geochemical and SrNd-Pb isotopic analysis. The results show that the ore-bearing porphyry of Dongwoodong ore district is 122 Ma in age, which is the product of the Early Cretaceous ore-forming event. The Sr-NdPb isotopic composition (Sr initial value 0.7052-0.7062,143 Nd / 144 Nd ratio 0.512365 ~ (204) Pb, ~ (207) Pb / ~ (204) Pb, ~ 208 Pb / ~ (204) Pb ~ 18.691 ~ 18.823, 15.638 ~ 115.796 and 38.649 ~ 38.924, respectively, revealing obvious crust-mantle mixing in the magmatic source area of the ore-bearing porphyries, which may be derived from the submarine crust under subduction in the Banqui ocean. Potential and solve the mineral prospecting bottleneck. After comprehensively analyzing the results of mining geology, geophysical prospecting (1/1000000 magnetic method and middle-lift survey of rockets) and geochemical exploration (1/1000000 sediment measurement of water system), it is considered that Dongwoodong Mine Area There are good geological conditions for mineralization. The anomalous distribution of geophysical and geochemical phenomena is concentrated and the superimposition is good. There is an important potential for prospecting. It is suggested that the exploration should take the prospecting of the porphyry-epithermal copper polymetallic deposits.