| 胶东金矿成矿系列硫同位素研究 |
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| 引用本文：.1994.Sulfur isotope studies of the metallogenic series of gold deposits in Jiaodong(Eastern Shandong)area[J].Mineral Deposits,13(1):75~87 |
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| 中文摘要:胶东金矿的早晚两期成矿系列中，岩浆成因或在岩浆期即有天然水和表生矿质加入
的矿床，δ34S值均有自早而晚依次降低的规律。为重熔岩浆分异成矿理论和成矿系列的建立提供了重要证据。焦家式和某些晚期矿床，在形成矿液后有表生硫加入，扰乱了这一规律性。胶东群中的硫同位素没有达到均匀化，副变质岩偏重，而斜长角闪岩偏轻，接近陨石硫值，是近似原始岩浆的产物。 |
| 中文关键词:硫同位素 成矿系列 表生矿质 岩浆分异 深熔岩浆 |
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| Sulfur isotope studies of the metallogenic series of gold deposits in Jiaodong(Eastern Shandong)area |
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| Abstract:The endogenic gold deposits in Jiaodong area might be assigned to two metallogenic epochs: principal(late Jurassic)epoch and accompanying(Early Cretaceous)eooch, resulting both from the differentiation and evolution of anatectic magma. In each epoch of the metallogenic series, δ34S values tend to decrease gradually from early to late, while things are quite the opposite for δ34 O values. The anatectic magma formed in the principal mineralization epoch occurred in larger depth, andδ34S values are somewhat high, varying from 8.9‰ of the granite through 6.9‰ of the intermediate-basic dikes to 6.7‰ of the gold deposits. In contrast, the anatectic magma formed in the accompanying mineralization epoch occurred in shallower place, and the process of its forma tion was characterized by the participation of meteoric water and exogenic ore substances; as a result, itsδ34S values are slightly lower, varying from 6.6‰ of the early granodiorite through 2.4‰ of the intermediate-basic dikes to-2.6‰ of the ore deposits. These data demonstrate that sulfur isotope fraction mainly follows the principle of thermodynamic effect, Whereas oxygen isotope fractionation is chiefly restricted by the theorem of kinetic energy. All this has provided the important basis for the establishment of the metallogenic theory of differentiation and evolution of anatectic magma and the metallogenic series. The Jiaojia type gold deposits Occur in large-size and gently-dipping rectonic shatter zones where large quantities of meteoric water and exogenic ore substances are stored. Once connecting with ore magma, the meteoric water and exogenic ore substance would particicipate in the ore-forming process. After the ore magma was trapped under great confining pressure, exogenic sulfur would be mixed and exchanged with magma sulfur i n a reducing environment. The equilibrium temperature between galena and sphalerite would remain stable at the end of the principal ore-forming stage. Hence theδ34S values of the Jiaojia type deposits obviously deviate toward the positive side. The participation of exogenic sulfur to the ore-forming process has confused the regularity of sulfur isotope evolution. |
| keywords:sulfur isotope, metallogenic series, supergene ore material, magmatic differentiation, anatectic magma |
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