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通过同位素地球化学研究,五台山—恒山一带金、银多金属矿床的硫源均来自深源;铅同位素组成表明成矿物质主要来自下地壳及地幔,但绿岩型金矿铅同位素变化较大,而燕山期次火山岩型金、银多金属矿床铅同位素较为集中;运移形成矿物的水源也有所不同,前者是以变质水为主(δ18OH2O1 34%～12 55%,δD-22 287%～-177 36%),后者则是以岩浆水及天水混合为主(δ18OH2O多在-18 6‰～+10 05‰,δD-68‰～-110‰);碳氧同位素组成也揭示了前者以变质作用为主(δ13C(PDB)-1 25‰～1 37‰,δ18O(SMOW)11 4%～16 5%),后者与花岗斑岩侵入有关(δ13C(PDB)为-4 0‰～-9 2‰,δ18O(SMOW)3 5‰～9 6‰);两类矿床的锶同位素比值,也反映了与成矿作用有着密切关系的太古宙斜长角闪岩和燕山中期花岗斑岩均是壳幔混合产物,故可视为两类矿床有着内在成因联系;钐-钕同位素组成不仅获得相同结论,而且从εNd(0)和fSm/Nd均是负值,推测属大陆地壳岩石,可能为O-C型绿岩地体的成矿背景,从而建立了五台热幔柱构造的成矿模型,试图指导找矿.
Through isotope geochemical studies, the sulfur sources of the gold and silver polymetallic deposits in the Wutaishan-Hengshan area originate from deep source. The lead isotopic composition indicates that the ore-forming materials mainly come from the lower crust and the mantle. However, the Pb isotope variation of the greenstone gold deposit changes greatly, The lead isotopes of the Yanshanian volcanic gold-silver and silver-polymetallic deposits are relatively concentrated. The water sources for migration and formation of minerals are also different. The former is dominated by metamorphic water (δ18OH2O1 34% -12 55%, δD-22 287% 177 36%). The latter is mainly composed of magmatic water and Tianshui (δ18OH2O mostly between -18 6 ‰ ~ + 105 ‰, δD-68 ‰ ~ -110 ‰). The composition of carbon and oxygen isotopes also revealed that the former Metamorphism (δ13C (PDB) -1 25 ‰ ~1 37 ‰, δ18O (SMOW) 11 4% ~16 5%), which is related to granite porphyry intrusion (δ13C (PDB) -4 0 ‰ ~ -9 2 ‰, δ18O (SMOW) 3-5 ‰ ~ 9 6 ‰). The strontium isotope ratio of two types of deposits also reflects that the Archean plagioclase amphibolite and Yanshan medium granite are closely related to the mineralization The porphyries are all mixed products of crust and mantle, so they can be regarded as the intrinsic genetic relationship between two types of deposits. The samarium-neodymium isotopic composition not only obtains the same conclusion, but also from εNd (0) and fSm / N d are all negative values. It is speculated that it belongs to the continental crustal rocks and may be the ore-forming background of the O-C type greenstone. Therefore, a metallogenic model of the Wutai thermal plume structure was established in order to guide ore prospecting.