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通过国内外花岗岩体的207对角闪石-黑云母40Ar-39Ar年龄(tAr)与锆石U-Pb年龄(tZr)之间差值(Δt=tZr-tAr)进行的频数统计分析表明:Δt呈对称正态分布(偏度系数CSK==-0.193;峰度系数CKU=16.9);年龄差(Δt)既呈正值又有负值,其众数值为0.40Ma,均值为0.45Ma。采用最小二乘法计算,花岗岩体锆石U-Pb年龄与花岗岩角闪石-黑云母40Ar-39Ar年龄拟合出相关系数很高(R=0.995)、回归系数接近l(0.997 7)的线性回归方程(tAr=0.997 7×tZr+0.004 5)。这些统计特征表明,从总体来看,花岗岩角闪石-黑云母40Ar-39Ar定年测定结果与锆石U-Pb定年测定结果是一致的,也不存在“花岗岩角闪石40Ar-39Ar年龄>黑云母40Ar-39Ar年龄”的规律。
Based on the statistical analysis of the frequency difference (Δt = tZr-tAr) between 207 diagonal amphibole-biotite 40Ar-39Ar ages (tAr) and zircon U-Pb ages (ΔT = tZr-tAr) (Skewness coefficient CSK == - 0.193; kurtosis coefficient CKU = 16.9). The age difference (Δt) showed positive and negative values with a mode of 0.40Ma and a mean of 0.45Ma. According to the least-square method, the U-Pb ages of granite bodies fit well with the ages of 40Ar-39Ar of hornblende-biotite of granite (R = 0.995), and the regression coefficients are close to l (0.997 7) Equation (tAr = 0.997 7 × tZr + 0.004 5). These statistical characteristics show that the results of 40Ar-39Ar dating of the granitoid amphibole-biotite are consistent with those of the zircon U-Pb dating, and there is no “40Ar-39Ar age of granite amphibole> Biotite 40Ar-39Ar age ”rule.