中文摘要:凤-太矿田和柞-山矿田分别位于秦岭泥盆系层状多金属成矿带的中段和东段。风凤-太矿田主要容矿岩石为硅质岩，其δ30Si、δ18O分别为-0.6‰～-0.3‰；18.6‰～21.0‰。矿床的δ34S值大部分位于4.9‰～11.3‰之间。柞-山矿田容矿岩石类型复杂，除硅质岩外尚有钠长石岩、黑云方柱石岩等，Na、Cl含量很高。容矿硅质岩的δ30Si、δ18O分别为-0.2‰~0.1‰、19.0‰～19.6%。矿床的δ34Si多为高正值，变化范围大，-3.5‰～33.7‰。文中指出两个矿田的矿床均由海底喷气作用形成，其中凤-太矿田形成于半封闭-半开放的环境，成矿温度低（约92℃），矿质堆积速度较慢；而柞-山矿田成矿早中期为一封闭海藏，晚期变为开放；成矿温度、矿质堆积速度相对较高；成矿早期有火山活动。
Abstract:Silicon, oxygen and sulfur stable isotope compositions and their variation regularity in Devonian stratiform Pb-Zn deposits of Feng-Tai and Zha-Shan orefields are studied in this paper. δ34Si values and δ18O values of ore-bearing siliccous rocks in the Feng-Tai orefield range form -0.6‰ to -0.3‰ and from 18.6‰ to 21.0‰ respectively. Similar to δ30Si and δ18O of siliceous rocks formed in hot spring and by submarine exhalition, δ30Si and δ18O of the siliceous rocks in the Feng-Tai orefield indicate a submarine exhalation origin. δ30Si values of the ore quartz veins are the same as those of ore-bearing siliceous rocks, suggesting that the ore quartz veins were formed as a result of remobilization and recrystallization of siliceous rocks. δ30Si and δ18O of the ore-bearing siliceous rocks in the Zha-Shan orefield range from -0.2‰ to 0.1‰ and from 19.0‰ to 19.6‰ respectively. The authors consider that the ore deposits in the Zha-Shan ore field were also formed by submarine exhalation, with however higher ore-forming temperature and deposition speed than those in the Feng-Tai orefield. δ34S values of the principal orebodies are mostly 10‰～30‰; δ34S values of barite in the ore deposit are even higher, ranging 22.3‰～33.7‰. Nevertheless, some small lead orebodies above the principal orebodies have relatively low δ34S values ( -3.5‰～4.0‰, 0.6‰ on the average). It is pointed out in the paper that sulfur in the ore deposits was exclusively derived from sulfates in sea water, and that the Zha-Shan basin was turned from an enclosed basin at the early (principal) ore-forming stage into an open basin at the late ore-forming stage. δ34S values of ore deposits in the Feng-Tai orefield are somewhat lower (4.9‰~11.3‰), implying a semi-open to semi-closed basin.
文章编号：
中图分类号：
文献标志码：
基金项目:国家自然科学基金资助项目（49103039）
引用文本：
李延河，蒋少涌，薛春纪.1997.秦岭凤-太矿田与柞-山矿田成矿条件及环境的对比研究[J].矿床地质,16(2):170~180.1997.A comparative study of ore-forming environments and conditions in Feng-tai and Zha-shan orefields, Qinling Mountains[J].Mineral Deposits16(2):170~180
图/表
