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对滇西兰坪盆地内金满脉状铜矿床成矿主阶段的石英样品进行了40Ar 39Ar快中子活化测定,谱线特征为马鞍型,其坪年龄为(58 05±0 54)Ma,最小视年龄为(56 76±0 81)Ma,等时线年龄为(54 30±0 15)Ma,三者均十分接近,说明所测石英样品的年龄可靠。而石英的流体包裹体Rb Sr同位素分析数据因线性关系不太好,导致等时线年龄(68±76)Ma误差大,因而仅具参考意义。砂岩及矿化砂页岩中磷灰石的裂变径迹年龄为58 7～61 7Ma,反映了兰坪盆地内一期构造热演化事件的发生时间,其与40Ar 39Ar分析的年龄基本一致,说明金满脉状铜矿床的形成时代相当于喜马拉雅早期。结合滇西大区域内铜及其他矿种的成矿主要集中在喜马拉雅早期这一现象,认为滇西在此时期必定存在着诱发某种大规模成矿作用的关键因素,并在区域内统一制约着矿床的形成。
Quartz samples of the main metallogenic stage of the Jinman vein copper deposit in the Lanping basin of Yunnan Province were characterized by 40Ar 39Ar fast neutron activation. Their spectral characteristics were saddle-type with a plateau age of (58 05 ± 0 54) Ma , The minimum age was (56 76 ± 0 81) Ma, and the isochron age was (54 30 ± 0 15) Ma, all of which were close to each other, indicating that the quartz samples tested were of reliable age. The Rb Sr isotope analysis data of quartz fluid inclusions are not good because of the linear relationship, resulting in a large error of isochron age (68 ± 76) Ma, which is only of reference significance. The fission track age of apatite in sandstone and mineralized shale is 587 ~ 61 7Ma, which reflects the occurrence time of the first-stage thermal evolution events in the Lanping basin, which is basically consistent with the age of the 40Ar 39Ar analysis The formation of the Golden Manian vein copper deposit is equivalent to the early Himalayas. The combination of copper and other mineral deposits in the western Yunnan mainly concentrates on the early Himalayan mineralization. It is believed that there are bound to exist some key factors that lead to some large-scale mineralization in western Yunnan during this period, The formation of the deposit.