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报道了塔里木盆地北部下寒武统底部黑色页岩的Re-Os和Nd同位素地球化学特征,并通过其Re-Os和Nd同位素特征探讨了该黑色页岩的物源性质.塔里木盆地北部下寒武统底部黑色页岩的Re/Os比值为7.18;187Re/188Os为5.6438;187Os/188Os为1.9616.这些特征反映了该黑色页岩具有壳源性质.其εNd(0)值为-13.17,εNd(540Ma)值为-7.32;Nd模式年龄TDM集中在1.535Ga.黑色页岩中Nd同位素的这些特征与盆地基底岩石的Nd同位素参数十分吻合.综合Re-Os和Nd同位素特征,说明塔里木盆地北部下寒武统底部的这套黑色页岩的物源中应包括以盆地基底为主要组成的大陆地壳.同时,通过与扬子地台下寒武统底部黑色页岩Re-Os同位素的对比,发现两者之间存在着较大的不同,可能反映了两者在沉积背景上的差异.这为正确分析塔里木地台与扬子地台的成因关系提供了Re-0s同位素方面的信息.
The Re-Os and Nd isotopic geochemical characteristics of the Lower Cambrian black shales in northern Tarim Basin are reported, and the provenance characteristics of the black shale are discussed by the Re-Os and Nd isotopic characteristics. The Re / Os ratios of the black shales at the bottom of the Wudang System are 7.18, 187Re / 188Os are 5.6438, and 187Os / 188Os are 1.9616. These features reflect the crustal nature of the black shale with εNd (0) of -13.17 and εNd (540Ma) is -7.32, and the TDM of Nd mode is concentrated at 1.535Ga. These characteristics of Nd isotopes in black shale are in good agreement with the Nd isotopic parameters of basement rocks. Based on the characteristics of Re-Os and Nd isotopes, The provenance of this black shale at the bottom of the Lower Cambrian should include the continental crust, which is mainly composed of the basins of the basin. At the same time, by comparing with the Re-Os isotopes of the black shale at the bottom of the Lower Cambrian in the Yangtze Platform, There is a big difference between the two, which may reflect the differences in sedimentary background between the two, which provides information on the Re-0s isotope for the correct analysis of the genetic relationship between the Tarim platform and the Yangtze platform.