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泰尔贝里矿床位于瑞典北部谢莱夫特地区,是一个相当于显生宙斑岩型矿床的元古代矿床。矿化带位于约恩花岗杂岩内,并与侵入的石英-长石斑岩有关。花岗质岩石与赋存块状硫化物矿床的长英质火山岩同期。蚀变通常是千枚-绿磐岩型,但金矿化区为千枚岩型。矿石矿物有黄铁矿、黄铜矿、闪锌矿、磁铁矿和极少量的辉钼矿。进行稳定同位素研究的石英、绢云母和绿泥石样品主要取自蚀变带。研究结果表明:岩浆石英δ~(18)O组成为+6.2～+6.7‰,热液蚀变石英δ~(18)O值为+7.5～+10.6‰。绢云母δ~(18)O值为+4.6～+8.2‰(平均+6.6‰),δD值为—31～—54‰(平均—41‰)。绿泥石δ~(18)O值为+4.2～+7.7‰,δD值为—34～—44‰。11个黄铁矿样品的δ~(34)S值为+3.8～5.5‰(平均+4.6±5‰)。模拟计算出与矿物平衡的水的同位素组成,其早期岩浆流体的δ~(18)O约为6.5‰,这种流体曾与一种被认为是海水的低δ~(18)O和高δD流体混合过。绢云母和绿泥石的δ~(18)O也说明有显著的水-岩交换,从而解释了与含水矿物平衡的水的δ~(18)O为正值的现象。
The Terburi deposit is located in the area of Skellefteh, northern Sweden, and is a Proterozoic deposit equivalent to the Phanerozoic porphyry deposits. The mineralized belt is located within the Jorn granite and is associated with intrusive quartz-feldspar porphyry. Granitic rocks are associated with the felsic magmatic rocks that hosted massive sulphide deposits. The alteration is usually a thousand-green rock type, but the gold mineralization area is phyllite type. Ore minerals are pyrite, chalcopyrite, sphalerite, magnetite and a very small amount of molybdenite. Quartz, sericite and chlorite samples for stable isotope studies are mainly taken from alteration zones. The results show that the δ 18 O composition of magmatic quartz is + 6.2 ~ + 6.7 ‰ and the δ 18 O value of hydrothermal altered quartz is + 7.5 ~ + 10.6 ‰. The sericite δ 18 O values ranged from + 4.6 to + 8.2 ‰ (+6.6 ‰ averagely), and δD values ranged from -31 to -54 ‰ (-41 ‰). The chlorite δ 18 O value is + 4.2 ~ + 7.7 ‰, and the δD value is -34 ~ -44 ‰. The δ ~ (34) S values of 11 pyrite samples ranged from + 3.8 to 5.5 ‰ (average + 4.6 ± 5 ‰). The isotopic compositions of water equilibrated with minerals were simulated. The δ 18 O values of the early magmatic fluids were about 6.5 ‰. This fluid was associated with a low δ 18 O and high δ D Fluid mixed. Δ ~ (18) O of sericite and chlorite also shows significant water-rock exchange, which explains the positive δ 18 O of water equilibrated with hydrous minerals.