Title Page
Contents
Abstract 7
1. Introduction 8
2. Material and Methods 13
2.1. Ice core samples 13
2.2. Sample preparation procedure 16
2.3. SEM/EDX measurements 19
2.4. Mineral identification 21
2.5. Calculation of the Chemical Index of Alteration (CIA) 24
3. Results and Discussion 37
3.1. Particle morphology 37
3.2. Mineral compositions 40
3.3. CIA values 45
3.4. Temporal variations in dust source regions across the Allerød/YD transition and associated potential climate factors 51
4. Conclusion 55
References 56
Table 1. Specific information on the GRIP ice core samples examined in this study. 15
Table 2. Specific information on the PSA samples used in this study and their major element compositions (wt%) and CIA values. 27
Table 3. Mineralogical abundances (%) and kaolinite-to-chlorite (K/C) ratio of the GRIP ice core samples examined in this study. 43
Table 4. Mass concentration of oxides (wt%) and CIA values (mol/mol%) of the GRIP ice core samples examined in this study. 50
Figure 1. Location of Greenland ice cores: GRIP (Greenland Ice Core Project), GISP2 (Greenland Ice Sheet Project 2), NGRIP (North Greenland... 14
Figure 2. SEIs from SEM of Al-coated Ag foil (a) before and (b) after loading UPW droplets on the same area. 19
Figure 3. The general scheme for retrieving insoluble particles from the GRIP ice core samples and the measurement procedure of individual... 21
Figure 4. Typical X-ray spectra of quartz, feldspars, kaolinite, chlorite, Fe- oxides, and TiO₂ observed in the GRIP ice core samples. 23
Figure 5. A-CN-K ternary diagram in molecular proportions with CIA values for the PSAs for Greenland dust and upper continental crust (UCC,... 36
Figure 6. Typical SEIs of quartz, feldspars, kaolinite, chlorite, Fe-oxides, and TiO₂ observed in the GRIP ice core samples. 38
Figure 7. Size distribution of insoluble particles in the GRIP ice core samples and log-normal fitting result. 39
Figure 8. (a) GRIP δ¹⁸O (Greenland temperature proxy) record throughout the Allerød/YD transition (Johnsen et al., 1997). The vertical solid yellow... 47
Figure 9. A-CN-K ternary diagram in molecular proportions with CIA values for the GRIP ice core samples spanning the periods (a) before and (b)... 49