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采用真空击碎技术提取东川汤丹铜矿床石英流体包裹体进行40Ar-39Ar法年龄测定，获得了逐渐下降的阶梯形年龄谱，表明流体包裹体含有过剩氩;数据点在40Ar／36Ar-39Ar／36Ar图解上构成等时线，等时线年龄为（712±33）Ma，代表了矿床的形成年龄。随后对其粉末进行40Ar-39Ar阶段加热（100—800℃）分析，形成相对比较平坦的年龄谱，坪年龄为（317±6）Ma（39Ar占45％，含真空击碎分析在内），粉末加热分析全部数据点构成的等时线年龄为（321±13）Ma。电子探针分析和显微镜观察证实了该石英样品中含有粒径大于100μm，K2O含量为8％-10％，形成时间明显晚于石英的白云母类富钾矿物，粉末阶段加热分析结果表明～320Ma应为后期白云母类矿物的年龄。
The quartz 40Ar-39Ar method was used to extract the quartz fluid inclusions from the Tongchuan copper deposit in Dongchuan by vacuum crushing. The descending ladder-shaped age spectrum was obtained, indicating that the fluid inclusions contained excess argon. The data points were at 40Ar / 36Ar- The isochrons are formed on the 39Ar / 36Ar plot, with an isochron age of (712 ± 33) Ma, representing the age at which the deposit was formed. Subsequently, the 40Ar-39Ar stage heating (100-800 ℃) analysis of the powder was carried out to form a relatively flat age spectrum of (317 ± 6) Ma (39Ar 45%, including vacuum crushing analysis) The isochron age of all data points in the powder heating analysis was (321 ± 13) Ma. Electron microprobe analysis and microscopic observation confirmed that the quartz sample contains muscovite-rich muscovite mica with particle size of more than 100μm, K2O content of 8% -10% and formation time significantly later than that of quartz. The results of heating in powder stage show that ~ 320Ma Should be the late muscovite mineral age.