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通过对南秦岭武当地块内变形变质基性岩墙群中的角闪石、黑云母矿物的４０Ａｒ－３９Ａｒ定年，获得角闪石三组年龄，分别为高温坪年龄６９４．４±２１Ｍａ，中温坪年龄３８４．４±３Ｍａ（相应等时线年龄为３８３．３±１０Ｍａ）和低温视年龄２４０～１８０Ｍａ。黑云母单一坪年龄为２３５．３±２Ｍａ（相应等时年龄为２３６．７±６Ｍａ）。结合本区基性岩墙已获得的Ｓｍ－Ｎｄ全岩等时年龄（７８２±１６４Ｍａ）分析，７８２±１６４Ｍａ～６９４．４±２１Ｍａ代表岩墙侵位、冷却过程的时间，提供了武当地块裂解的构造事件年龄；３８４．４±３Ｍａ和约２４０Ｍａ则代表岩墙群侵位后两期重要构造－热事件的改造年龄。上述为武当地块的构造作用过程和南秦岭构造带的形成、演化提供了重要证据。
Through the 40 Ar-39Ar dating of the amphibole and biotite minerals in the metamorphic and metamorphic basement dyke swarms in the Wudang block in the South Qinling Mountains, three groups of amphiboles were obtained: the high-temperature ping age of 694.4 ± 21Ma, the medium temperature Ping age 384.4 ± 3Ma (corresponding isochron age of 383.3 ± 10Ma) and low temperature as the age of 240 ~ 180Ma. The average age of biotite was 235.3 ± 2Ma (corresponding to an isochron age of 236.7 ± 6Ma). Based on the analysis of the Sm-Nd whole-rock isochron age (782 ± 164Ma) obtained from the basic dyke in this area, the time of emplacement and cooling of the dyke wall is 782 ± 164Ma ~ 694.4 ± 21Ma, The ages of the tectono-pyramidal event are 384.4 ± 3Ma and about 240Ma, representing the ages of two important tectono-thermal events after emplacement of the dike. The above provides important evidences for the tectonic process of the Wudang block and the formation and evolution of the South Qinling structural belt.