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通过对瑞典北部和芬兰中部三个地区的早元古代金矿中方铅矿的铅同位素成分的测定,可以知道这些金矿床的容矿主岩是由一系列年龄为1870—1890Ma的瑞芬系(元古代)岩石组成,包括谢莱夫特地区(瑞典)岛弧火山沉积岩序列及约恩(瑞典)和“北部低地”(芬兰)的Ⅰ-型英云闪长岩。这些与瑞芬系岩石有关的矿床是后生的,它们构成与太古界域西南边界相平行的绵延600km的含金成矿带的一部分。不管这些矿床的后生关系如何,铅同位素数据表明这些矿床的年龄与1870—1890Ma的瑞芬系岩石年龄相比,并不明显年轻多少(可能相差不超过10～20Ma)。在金矿床形成过程‘},有两个主要的铅源被活化。最主要的来源是I一型英云闪长岩,它构成了整个成矿带中一个相对原始的(林~9.3)且广泛分布的金来源。此外,谢莱夫特地区最西端的火山岩则构成r另一个极端原始的(。<9.0)金属源,不过后者仅在局部地区对该成矿带中的后生矿床提供重要的金属来源.通过对这些有明显不同铅源的铅同位素成分的测算,可以知道谢莱夫特地区西部的火山岩与约恩和芬兰,},部的卜型英云闪长岩并不是同岩浆源的。
Based on the determination of Pb isotopic composition of the Chinese galena from the Early Proterozoic gold deposits in the three areas of northern Sweden and central Finland, it is known that the host rocks of these gold deposits are dominated by a series of Reifen series (1870-1890 Ma) Proterozoic) rocks, including the sequence arc volcanic sedimentary rocks in the Skellefteh area (Sweden) and the type I-type diorites of Jorn (Sweden) and the “Northern Lowland” (Finland). These deposits related to the Reeufen system are epigenetic and form part of a 600 km gold-bearing metallogenic belt parallel to the southwestern boundary of the Archean Terrain. Regardless of their epigenetic relationship, lead isotopic data suggest that the age of these deposits is not significantly younger (probably less than 10-20 Ma) compared to the age of the Reifenite rocks of 1870-1890 Ma. During the formation of gold deposits, two major lead sources are activated. The most important source is I-type diorite, which forms a relatively primitive (~ 9.3 forest) gold source widely distributed throughout the metallogenic belt. In addition, volcanic rocks in the westernmost part of the Skellefte r constitute another extremely primitive (. <9.0) metal source, although the latter only provides localized metal sources for the epigenetic deposits in the metallogenic belt. The calculation of the Pb isotopic composition of these obviously different lead sources shows that the volcanic rocks in the western Ley Skift and the Jönning and Finland, are not the same magmatic source as the Bu-Ying diorites.