西藏明赛矿区绢云母40Ar/39Ar定年数据（2018-2022）

云母Ar-Ar测年技术将选取的白云母样品粉碎、过筛、手工淘洗、重液分离、磁力分选和显微镜检查等获取白云母单矿物，选纯的矿物（纯度>99％）用超声波清洗。清洗后的样品被封进石英瓶中送核反应堆中接受中子照射。照射工作是在中国原子能科学研究院的“游泳池堆”中进行的，使用B4孔道，中子流密度约为2.65×1013n cm-2S-1。照射总时间为1440分钟，积分中子通量为2.30×1018n cm-2；同期接受中子照射的还有用做监控样的标准样：ZBH-25黑云母标样，其标准年龄为132.7±1.2Ma，K含量为7.6%。样品的阶段升温加热使用石墨炉，每一个阶段加热10分钟，净化20分钟。质谱分析是在多接收稀有气体质谱仪Helix MC上进行的，每个峰值均采集20组数据。所有的数据在回归到时间零点值后再进行质量歧视校正、大气氩校正、空白校正和干扰元素同位素校正。中子照射过程中所产生的干扰同位素校正系数通过分析照射过的K2SO4 和CaF2来获得，其值为：（36Ar/37Aro）Ca =0.0002398，（40Ar/39Ar）K=0.004782，（39Ar/37Aro）Ca =0.000806。37Ar经过放射性衰变校正；40K衰变常数λ＝5.543×10-10年-1；计算的J值为0.003283。主成矿期热液载金绢云母40Ar-39Ar年龄为16.03±0.31 Ma，表明该矿床形成于中新世，明显不同于特提斯喜马拉雅金锑多金属成矿带中主要金矿床（形成于始新世）。

The mica ⁴⁰Ar-³⁹Ar dating technique involves processing selected muscovite samples through crushing, sieving, hand panning, heavy liquid separation, magnetic separation, and microscopic examination to obtain single muscovite minerals. The purified minerals (purity > 99%) were cleaned using ultrasonic waves. The cleaned samples were sealed in quartz vials and sent to a nuclear reactor for neutron irradiation. The irradiation was conducted at the swimming pool reactor of the China Institute of Atomic Energy (CIAE), using the B4 beam port, with a neutron flux density of approximately 2.65×10¹³ n cm⁻² s⁻¹. The total irradiation time was 1440 minutes, with an integrated neutron flux of 2.30×10¹⁸ n cm⁻². Simultaneously irradiated as a monitor standard was the ZBH-25 biotite standard, with a certified age of 132.7±1.2 Ma and a K content of 7.6%. Stepwise heating of the samples was performed using a graphite furnace, with each heating stage lasting 10 minutes followed by a 20-minute purification period. Mass spectrometric analysis was carried out on a multi-collector rare gas mass spectrometer Helix MC, with 20 sets of data collected for each peak. All data were first regressed to the time-zero value, followed by mass discrimination correction, atmospheric argon correction, blank correction, and interfering element isotope correction. The correction coefficients for interfering isotopes generated during neutron irradiation were obtained by analyzing irradiated K₂SO₄ and CaF₂, with the values as follows: (³⁶Ar/³⁷Ar)Ca = 0.0002398, (⁴⁰Ar/³⁹Ar)K = 0.004782, (³⁹Ar/³⁷Ar)Ca = 0.000806. ³⁷Ar was corrected for radioactive decay; the decay constant of ⁴⁰K, λ = 5.543×10⁻¹⁰ a⁻¹, and the calculated J value was 0.003283. The ⁴⁰Ar-³⁹Ar age of hydrothermal gold-bearing sericite from the main mineralization period is 16.03±0.31 Ma, indicating that the deposit formed in the Miocene, which is distinctly different from the major gold deposits in the Tethyan Himalayan gold-antimony polymetallic metallogenic belt, which formed during the Eocene.

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该数据集提供了西藏明赛矿区绢云母的40Ar/39Ar定年数据，详细记录了样品的制备和分析过程，主成矿期热液载金绢云母的年龄为16.03±0.31 Ma，表明矿床形成于中新世。数据以Excel表格形式存储，便于直接使用和分析。