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本文对两个北秦岭丹凤群斜长角闪岩样品进行了Ｓｍ－Ｎｄ、Ｒｂ－Ｓｒ和４０Ａｒ／３９Ａｒ测年，发现其中受构造改造轻微的黑河丹凤群斜长角闪岩样品的角闪石４０Ａｒ／３９Ａｒ年龄与其Ｒｂ－Ｓｒ、Ｓｍ－Ｎｄ矿物等时线年龄接近，而遭受强烈构造剪切作用的蒲峪丹凤群斜长角闪（片）岩的角闪石４０Ａｒ／３９Ａｒ年龄则明显高于其Ｒｂ－Ｓｒ、Ｓｍ－Ｎｄ矿物等时线年龄，指示构造剪切作用对变质角闪石中过剩氩的引入有显著影响。在利用４０Ａｒ／３９Ａｒ进行造山带年代学研究时这一问题应引起注意
In this paper, the Sm-Nd, Rb-Sr and 40Ar / 39Ar dating of the Danfeng Group amphibolites in the North Qinling Mountains are studied. The results show that the angle of the amphibolites from the Danfeng Group in Heihe The 40Ar / 39Ar ages of amphiboles are similar to those of the Rb-Sr and Sm-Nd minerals, and the 40Ar / 39Ar ages of amphiboles of the Puyuodanfeng group plagioclase in the intense tectonic shear It is obviously higher than the isochron age of the Rb-Sr and Sm-Nd minerals, indicating that the tectonic shear effect has a significant effect on the excess argon introduced into the metamorphic hornblend. This issue should be noted when using 40Ar / 39Ar for orbital chronology