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我们对瑞典中部伯斯莱根地区早元古代瑞典—卡累利阿的三个层控硫化矿床,以及埃尔夫达伦和万斯伯罗地区早—中元古代,晚于瑞卡地带内四个再生矿床的方铅矿进行了铅同位素测定。伯斯莱根层控矿床在广大地区显示出铅同位素的均一性。这样的同位素组成,表明在本区存在着早于瑞卡的地层,并与活动的大陆边缘环境中的喷气沉积矿层相一致。在万斯伯罗和埃尔夫达伦地区各自的铅同位索组成也是一致的,但两个地区之间有明显的差异。这样的同位素组成表明铅的来源,不仅来自再循环的瑞卡地层中的铅,而且有来自幔源的原生铅。这里许多矿床的模式年龄和地质年龄不同,放射性成因的铅略为超过,这就表明芬诺斯堪的亚地盾铅的分配与常规的全球铅演化模式有显著的不同。
We conducted three stratigraphic-controlled sulphide deposits of the early Proterozoic Sweden-Karelia in the region of Baslerengen in central Sweden, and early-mid-Proterozoic and later-dated Ruika areas in the Elfdren and Vanspar regions Galena from four reclaimed deposits were subjected to lead isotopic measurements. The Beursley stratigraphic deposit shows the uniformity of lead isotopes in a wide area. This isotopic composition indicates that there is a pre-Rika formation in this area and is consistent with the jet-laden seam in the active continental margin. The same lead isotopic composition is also found in the Vanspar and Elfdrum regions, but there is a clear difference between the two regions. Such isotopic composition indicates the source of lead, not only from the recycled Rica strata but also from the mantle source. The pattern ages and geologic age of many deposits are different here, and lead in radiogenic genesis slightly exceeds this, indicating that there is a significant difference between the distribution of lead in Fenn Scandinavian shields and the conventional global lead evolution pattern.