Description
The supplementary file is embargoed until 20/02/20, in line with the post-print. The file contents are Supplementary Tables S1-S6, and Supplementary Figure S1:
Supplementary Table 1. Stable isotope and trace element results table.
Supplementary Table 2. Laser Ablation U-Pb analytical data for Hoogland X4.
Supplementary Table 3. (a) Hoogland X4 U activity measurements. (b) Correction of the Hoogland X4 isotope dilution 238U/206Pb isochron age (Figure 7b) using four different initial 234U/238U ratio scenarios. These scenarios include correction using the mean measured U activity ratio (Table S3a), and correction using an assumed initial [U] of 1, 1.3 and 1.9. The latter two values are plausible initial [U] values taken from the compilation of initial 234/238U ratios calculated from U-Th dated Cradle of Humankind speleothems (see Table S6). The initial [U] value of 1.3 ± 0.3, and corresponding age of 5.28 ± 0.12 Ma (bold) is our favoured scenario. (M) refers to Measured values, (C) refers to Calculated values and (A) refers to Assumed values.
Supplementary Table 4. U-Pb isotope dilution isotopic data for Hoogland X4 sample aliquots.
Supplementary Table 5. U-Pb LA-ICP-MS data for WC-1 calcite standard.
Supplementary Table 6. List of initial 234U/238U ratios from U-Th dated speleothems from the Cradle of Humankind.
Supplementary Figure S1. Graphical Plot of WC-1 standard calcite data for LA-ICP-MS.
Supplementary Table 1. Stable isotope and trace element results table.
Supplementary Table 2. Laser Ablation U-Pb analytical data for Hoogland X4.
Supplementary Table 3. (a) Hoogland X4 U activity measurements. (b) Correction of the Hoogland X4 isotope dilution 238U/206Pb isochron age (Figure 7b) using four different initial 234U/238U ratio scenarios. These scenarios include correction using the mean measured U activity ratio (Table S3a), and correction using an assumed initial [U] of 1, 1.3 and 1.9. The latter two values are plausible initial [U] values taken from the compilation of initial 234/238U ratios calculated from U-Th dated Cradle of Humankind speleothems (see Table S6). The initial [U] value of 1.3 ± 0.3, and corresponding age of 5.28 ± 0.12 Ma (bold) is our favoured scenario. (M) refers to Measured values, (C) refers to Calculated values and (A) refers to Assumed values.
Supplementary Table 4. U-Pb isotope dilution isotopic data for Hoogland X4 sample aliquots.
Supplementary Table 5. U-Pb LA-ICP-MS data for WC-1 calcite standard.
Supplementary Table 6. List of initial 234U/238U ratios from U-Th dated speleothems from the Cradle of Humankind.
Supplementary Figure S1. Graphical Plot of WC-1 standard calcite data for LA-ICP-MS.
| Date made available | 20 Feb 2019 |
|---|---|
| Publisher | Elsevier BV |