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武当地块基性岩墙群与耀岭河群基性火山岩的 Ｓｒ、 Ｎｄ、 Ｐｂ 同位素特征反映它们具相同的混合地幔源区。前者的（８７ Ｓｒ／８６ Ｓｒ）ｉ＝ ０６９０５～０７０６１， ε Ｎ ｄ （ｔ） ＝ － １９～５０， Δ２０８ Ｐｂ／２０４ Ｐｂ＝ ３５４９～１９０２６， Δ２０７ Ｐｂ／２０４ Ｐｂ＝ ４～８５， Ｔｈ／ Ｔａ 低， Ｌａ／ Ｙｂ 变化大；后者的（８７ Ｓｒ／８６ Ｓｒ）ｉ＝ ０６４８７～０７０７５，ε Ｎ ｄ（ｔ）＝ ０１１～３９４， Δ２０８ Ｐｂ／２０４ Ｐｂ＝ － ８１５８～２１９９５， Δ２０７ Ｐｂ／２０４ Ｐｂ＝ ４４４～１６６８， Ｔｈ／ Ｔａ 和 Ｌａ／ Ｙｂ 较高。这指示它们的源区以岩石圈亏损地幔和第２ 类富集地幔为主要混合组分， 耀岭河群基性火山岩曾遭受地壳物质的混染。结合它们具大陆拉斑玄武岩地球化学特征， 代表同源异相裂谷环境的产物推断， 南秦岭基底陆块在新元古代时曾发生过一次重要裂解作用， 并向早古生代秦岭洋盆转变。
The Sr, Nd and Pb isotopic characteristics of the basic dyke swarms in the Wudang block and the basic volcanic rocks in the Yao Ling River Group reflect the same mixed mantle source. The former (87 Sr / 86 Sr) i = 06905 ~ 07061, ε N d (t) = -19 ~ 50, Δ208 Pb / 204 Pb = 3549 ~ 19026, Δ207 Pb / 204 Pb = 4 ~ 85, Th / Ta low and La / Yb varied greatly; the latter 87 Sr / 86 Sr = 06487 ~ 07075 and ε N d (t) = 0 Δ208 Pb / 204 Pb = -8158 ~ 21995, Δ207 Pb / 204 Pb = 444 ~ 1668, and Th / Ta and La / Yb higher. This indicates that their source area is dominated by lithospheric depleted mantle and type 2 enrichment mantle, and the base volcanic rocks of the Yao Ling River Group have been contaminated by crustal material. Based on their geochemical characteristics of continental tholei basalts and the products representing the homogenous heterogeneous rift environment, they have undergone an important cleavage during the Neoproterozoic and have been transformed into the Qinling ocean basin of the Early Paleozoic.