【摘要】 对采自十八顷毫金矿区的黑云母、角闪石用阶段升温法进行40Ar／39Ar年龄谱研究，结合矿区地质特征，认为黑云母近似直线年龄谱的坪年龄（277Ma）及角闪石稳定坪年龄（288Ma）代表了韧性剪切带最新活动的时代；角闪石矿物年龄谱反映的后期热扰动（268Ma）反映区域退化变质作用发生的时代，269～277Ma的年龄可能代表了与退化变质同时的金矿化时代。更多还原

【Abstract】 The Shibaqinghao gold deposit is a typical one occurring in a ductile shear zone in centralInner Mongolia. To gain a better understanding of the age of gold mineralization and its relationship with the evolution of the ductile shear zone,40Ar/39Ar plateau age analysis was made on biotitefrom biotite-quartz gneiss and on hornblende from biotite-hornblende mylonite. The 40Ar/39Arplateau age spectra of biotite are represented by nearly a straight line. The age of 277. 23 Ma standsfor the age of gold mineralization and the latest retrograde metamorphism. The 40Ar/39Ar age spectra of hornblende are normal. The age of 268. 62 Ma means the latest activity of the ductile shearzone, and the age of 268. 5~277. 23 Ma may represent the age of gold mineralization contemperaneous with the retrograde metamorphism.更多还原