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Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Protocol used to measure pIRIR150_
| Step | Treatment | Observed |
|---|---|---|
| 1 | Dose | |
| 2 | Preheat at 180°C for 60 s | |
| 3 | IRSL measurement at 50°C for 100 s | Lx1 |
| 4 | IRSL measurement at 150°C for 200 s | Lx2 |
| 5 | Test dose | |
| 6 | Preheat at 180°C for 60 s | |
| 7 | IRSL measurement at 50°C for 100 s | Tx1 |
| 8 | IRSL measurement at 150°C for 200 s | Lx2 |
| 9 | Return to step 1 |
Luminescence dating results for six samples from CE1 profile_
| Section name | Sample ID | Depth (cm) | U (ppm) | Th (ppm) | K (%) | Water Content (%) | Cosmic dose rate (Gy/ka) | Total dose rate(Gy/ka) | De (Gy) | Age (ka) |
|---|---|---|---|---|---|---|---|---|---|---|
| CE1 | NL-1456 | 40 | 2.63±0.10 | 9.81±0.28 | 1.59±0.05 | 4.16±10 | 0.42±0.04 | 3.92±0.25 | 0.45±0.04 | 0.1±0.01 |
| NL-1457 | 90 | 2.1±0.09 | 7.02±0.22 | 1.00±0.04 | 10.70±10 | 0.39±0.04 | 3.72±0.26 | 29.70±0.2 | 7.9±0.5 | |
| NL-1458 | 150 | 3.89±0.14 | 9.58±0.28 | 1.44±0.05 | 10.86±10 | 0.36±0.04 | 4.08±0.26 | 33.23±0.4 | 8.0±0.5 | |
| NL-1459 | 170 | 5.87±0.21 | 6.85±0.23 | 1.03±0.04 | 30.74±10 | 0.35±0.04 | 3.56±0.25 | 27.49±0.6 | 7. 6±0.6 | |
| NL-1460 | 210 | 6.67±0.21 | 6.2±0.20 | 0.85±0.04 | 29.88±10 | 0.33±0.03 | 3.52±0.26 | 25.13±0.2 | 7.1±0.5 | |
| NL-1461 | 245 | 2.71±0.11 | 9.45±0.27 | 1.61±0.05 | 2.48±10 | 0.32±0.03 | 3.68±0.24 | 34.69±0.3 | 9.4±0.6 |
Summary of the AMS 14C ages_
| Sample ID | Depth (cm) | Material | Radiocarbon Age (a BP) | Calibrated Radiocarbon age (cal ka BP) |
|---|---|---|---|---|
| Beta-471695 | 162 | shell | 13060±30 | 15.6±0.1 |
| Beta-471698 | 0 | shell | 1320±30 | 1.3±0.04 |