图1   洛川黄土古土壤剖面及潜在物源区位置

Fig.1   Distribution of Chinese loess-paleosol deposits in Luochuan and potential source regions

图2   洛川黄土-古土壤剖面样品磁性地层(据参考文献[22-24]修改)

Fig.2   The magnetic poperties of the Luochuan loess-paleosol profile

图3   洛川黄土古土壤样品碎屑锆石U-Pb年龄分布图

Fig.3   Distribution of detrital zircon U-Pb ages for Luochuan Loess Paleosol samples

图4   洛川剖面(S0、L1、L2、S2、L15、L18、L22、L24、L29、L33)碎屑锆石U-Pb年龄数据的非矩阵多维标度(MDS)统计分析图

Fig.4   MDS plots of statistical analysis of detrital zircons U-Pb age data from the Luochuan profile(S0,L1,L2,S2,L15,L18,L22,L24,L29,L33)

图5   洛川剖面下段沉积(L18、L22、L24、L29、L33)以及黄土高原潜在物源区碎屑锆石U-Pb年龄数据的非矩阵多维标度(MDS)统计分析图

Fig.5   MDS plots of statistical analysis of detrital zircons U-Pb age data from the Luochuan profile(L18,L22,L24,L29,L33) and the samples of potential provenance regionsof Loess Plateau

图6   东毛乌素沙漠(E-MUS)和L18、L22、L24、L29、L33碎屑锆石U-Pb年龄对比分布图

Fig.6   A comparison of the distribution of detrital zircon U-Pb ages from Eastern Mu Us Desert(E-MUS) and L18,L22,L24,L29,L33

图7   洛川剖面下段沉积(L18、L22、L24、L29、L33)物源沉积过程(改编自参考文献[38-40])

Fig.7   Map of material source deposition process of the lower part (L18,L22,L24,L29,L33)of the Luochuan profile

图8   洛川剖面上段沉积样品(S0、L1、L2、S2、L15)及黄土高原潜在源区碎屑锆石U-Pb年龄数据的非矩阵多维标度(MDS)统计分析图

Fig.8   MDS plots of the upper part samples of Luochuan profile(S0,Ll,L2,S2,L15) and the samples of potential sourceof Loess Plateau

图9   弱水河下游河床(RSH01)与S0、L1、L2、L15锆石U-Pb年龄分布图

Fig.9   A comparison of the distribution of detrital zircon U-Pb ages from the Alxa mixture (RSH01)and S0,L1,L2,L15

图10   西毛乌素沙漠(W-MUS)和S2碎屑锆石U-Pb年龄分布对比图

Fig.10   A comparison of the distribution of detrital zircon U-Pb ages from Western Mu Us Desert(W-MUS) and S2

图11   洛川剖面上段沉积(S0、L1、L2、S2、L15)物质源区图

Fig.11   Map of material source of the upper part (S0,Ll,L2,S2,L15)of the Luochuan profile

表1   潜在物源区锆石年龄样品

Tab.1   Zircon U-Pb age samples from potential provenance regions

表2   洛川剖面各层位主要年龄分布段及所占比重

Tab.2   Main age distribution and proportion of each layer in Luochuan profileMa　

表3   主要年龄分布段

Tab.3   Main age distribution