# IntCal20 calibration of the Traversette mire radiocarbon dates

Source of the measurements: Mahaney et al. 2017, Archaeometry 59(1), Table 1 (p. 171); material: peat (p. 170). Calibration here: IntCal20 (Reimer et al. 2020), flat prior, no sequence model, HPD ranges. Authors' own values (IntCal13/OxCal 4.2.4) shown for comparison. Hannibal window = 230-200 BC (cal BP 2149-2179).

| Lab code | 14C BP | Depth (cm) | Bed (authors) | 68.3 % HPD (IntCal20) | 95.4 % HPD (IntCal20) | Median | P(230-200 BC) | P(220-215 BC) | Authors' 2-sigma (IntCal13, cal BP) |
|---|---|---|---|---|---|---|---|---|---|
| Beta-305008 | 1130 ± 30 | 26 | post-invasion beds (top of subsection I) | AD 913 to AD 975 (cal BP 1037-975, 56.0 %); AD 889 to AD 903 (cal BP 1061-1047, 12.8 %) | AD 875 to AD 992 (cal BP 1075-958, 88.3 %); AD 852 to AD 852 (cal BP 1098-1098, 0.1 %); AD 830 to AD 850 (cal BP 1120-1100, 3.7 %); AD 776 to AD 785 (cal BP 1174-1165, 3.3 %) | AD 930 | 0.0 % | 0.0 % | 1173-962 (AD 777 to AD 988) -- excludes 218 BC |
| UBA-24875 | 2070 ± 31 | 40 | MAD bed, upper part (40 cm) | 9 BC to 1 BC (cal BP 1958-1950, 5.4 %); 112 BC to 41 BC (cal BP 2061-1990, 55.6 %); 149 BC to 136 BC (cal BP 2098-2085, 7.7 %) | 169 BC to AD 8 (cal BP 2118-1942, 95.6 %) | 81 BC | 0.0 % | 0.0 % | 2125-1949 (176 BC to AD 1) -- excludes 218 BC |
| Ta-3021 | 2530 ± 90 | 40 | MAD bed, upper part (40 cm) | 654 BC to 542 BC (cal BP 2603-2491, 32.6 %); 709 BC to 661 BC (cal BP 2658-2610, 13.6 %); 796 BC to 717 BC (cal BP 2745-2666, 22.3 %) | 814 BC to 407 BC (cal BP 2763-2356, 95.5 %) | 635 BC | 0.0 % | 0.0 % | 2769-2357 (820 BC to 408 BC) -- excludes 218 BC |
| UBA-23647 | 3537 ± 28 | 45 | MAD bed, lower part (45 cm) | 1796 BC to 1778 BC (cal BP 3745-3727, 13.3 %); 1843 BC to 1822 BC (cal BP 3792-3771, 17.5 %); 1926 BC to 1876 BC (cal BP 3875-3825, 38.0 %) | 1756 BC to 1751 BC (cal BP 3705-3700, 0.6 %); 1854 BC to 1768 BC (cal BP 3803-3717, 45.6 %); 1952 BC to 1863 BC (cal BP 3901-3812, 49.2 %) | 1871 BC | 0.0 % | 0.0 % | 3895-3720 (1946 BC to 1771 BC) -- excludes 218 BC |
| Ta-3022 | 3270 ± 100 | 50 | MAD bed, lower part (50 cm) | 1637 BC to 1430 BC (cal BP 3586-3379, 64.9 %); 1670 BC to 1655 BC (cal BP 3619-3604, 3.4 %) | 1353 BC to 1299 BC (cal BP 3302-3248, 3.4 %); 1774 BC to 1372 BC (cal BP 3723-3321, 90.3 %); 1815 BC to 1804 BC (cal BP 3764-3753, 0.5 %); 1872 BC to 1847 BC (cal BP 3821-3796, 1.4 %) | 1552 BC | 0.0 % | 0.0 % | 3820-3249 (1871 BC to 1300 BC) -- excludes 218 BC |
| UBA-24876 | 3282 ± 28 | 50 | MAD bed, lower part (50 cm) | 1544 BC to 1507 BC (cal BP 3493-3456, 41.9 %); 1559 BC to 1556 BC (cal BP 3508-3505, 3.2 %); 1602 BC to 1581 BC (cal BP 3551-3530, 19.2 %); 1608 BC to 1604 BC (cal BP 3557-3553, 3.9 %) | 1619 BC to 1499 BC (cal BP 3568-3448, 95.4 %) | 1546 BC | 0.0 % | 0.0 % | 3573-3450 (1624 BC to 1501 BC) -- excludes 218 BC |
| Beta-305009 | 3170 ± 30 | 65 | pre-invasion beds (base of core, 65 cm) | 1456 BC to 1419 BC (cal BP 3405-3368, 47.2 %); 1495 BC to 1477 BC (cal BP 3444-3426, 21.4 %) | 1331 BC to 1328 BC (cal BP 3280-3277, 0.6 %); 1503 BC to 1398 BC (cal BP 3452-3347, 94.8 %) | 1447 BC | 0.0 % | 0.0 % | 3454-3345 (1505 BC to 1396 BC) -- excludes 218 BC |
| UBA-30324 | 1393 ± 49 | 22 | G5B, above churned zone (22 cm) | AD 605 to AD 666 (cal BP 1345-1284, 68.9 %) | AD 742 to AD 772 (cal BP 1208-1178, 7.9 %); AD 696 to AD 702 (cal BP 1254-1248, 1.0 %); AD 571 to AD 689 (cal BP 1379-1261, 86.6 %) | AD 643 | 0.0 % | 0.0 % | 0-0 (n/a to n/a) |
| UBA-30321 | 2678 ± 41 | 36 | G5B, churned zone (35-37 cm) | 839 BC to 802 BC (cal BP 2788-2751, 46.4 %); 896 BC to 872 BC (cal BP 2845-2821, 21.9 %) | 908 BC to 792 BC (cal BP 2857-2741, 95.5 %) | 837 BC | 0.0 % | 0.0 % | 0-0 (n/a to n/a) |
| UBA-30331 | 1842 ± 41 | 45 | G5C (45 cm) | AD 198 to AD 241 (cal BP 1752-1709, 34.6 %); AD 154 to AD 194 (cal BP 1796-1756, 25.3 %); AD 130 to AD 144 (cal BP 1820-1806, 8.9 %) | AD 283 to AD 327 (cal BP 1667-1623, 10.5 %); AD 117 to AD 256 (cal BP 1833-1694, 83.3 %); AD 85 to AD 95 (cal BP 1865-1855, 1.6 %) | AD 200 | 0.0 % | 0.0 % | 0-0 (n/a to n/a) |
| UBA-30330 | 2190 ± 35 | 51 | G5C (51 cm) -- authors' 218 BC bed at 50 cm | 188 BC to 176 BC (cal BP 2137-2125, 6.1 %); 231 BC to 195 BC (cal BP 2180-2144, 20.1 %); 355 BC to 282 BC (cal BP 2304-2231, 42.3 %) | 126 BC to 125 BC (cal BP 2075-2074, 0.2 %); 379 BC to 152 BC (cal BP 2328-2101, 95.2 %) | 274 BC | 17.2 % | 3.1 % | 0-0 (n/a to n/a) |
| UBA-30330b | 2523 ± 36 | 58 | G5C (58 cm) [lab number printed as UBA-30330 twice; sic] | 643 BC to 566 BC (cal BP 2592-2515, 39.0 %); 688 BC to 666 BC (cal BP 2637-2615, 12.7 %); 776 BC to 748 BC (cal BP 2725-2697, 16.8 %) | 655 BC to 541 BC (cal BP 2604-2490, 49.2 %); 710 BC to 661 BC (cal BP 2659-2610, 18.4 %); 793 BC to 716 BC (cal BP 2742-2665, 27.8 %) | 643 BC | 0.0 % | 0.0 % | 0-0 (n/a to n/a) |
| UBA-30318 | 1724 ± 38 | 35 | G5D (35 cm) | AD 396 to AD 402 (cal BP 1554-1548, 4.3 %); AD 387 to AD 392 (cal BP 1563-1558, 3.6 %); AD 327 to AD 382 (cal BP 1623-1568, 40.6 %); AD 256 to AD 283 (cal BP 1694-1667, 20.1 %) | AD 304 to AD 412 (cal BP 1646-1538, 65.3 %); AD 247 to AD 299 (cal BP 1703-1651, 30.2 %) | AD 338 | 0.0 % | 0.0 % | 0-0 (n/a to n/a) |
| UBA-30315 | 2329 ± 55 | 45 | G5D (45 cm) -- authors' 218 BC bed at 45 cm | 245 BC to 233 BC (cal BP 2194-2182, 4.1 %); 278 BC to 258 BC (cal BP 2227-2207, 6.3 %); 481 BC to 357 BC (cal BP 2430-2306, 56.6 %); 506 BC to 505 BC (cal BP 2455-2454, 0.5 %); 511 BC to 508 BC (cal BP 2460-2457, 1.0 %) | 316 BC to 204 BC (cal BP 2265-2153, 21.4 %); 545 BC to 347 BC (cal BP 2494-2296, 70.0 %); 662 BC to 651 BC (cal BP 2611-2600, 1.3 %); 732 BC to 697 BC (cal BP 2681-2646, 2.8 %) | 400 BC | 3.6 % | 0.9 % | 0-0 (n/a to n/a) |

## The two dates from the 40 cm level (the 'bracketing' pair)

UBA-24875 (2070 ± 31 BP) and Ta-3021 (2530 ± 90 BP) come from the same depth. Ward & Wilson test: weighted mean 2119 ± 29 BP, T = 23.35 (df = 1, critical value 3.84 at 5 %), p = 1.3e-06. They are NOT statistically consistent: they cannot be two measurements of one true age. Either the level contains peat of two different ages (reworking), or one measurement is wrong.

Mass of each 40 cm date in the 230-200 BC window: UBA-24875 0.0 %, Ta-3021 0.0 %

Curve at 218 BC: 14C age 2216 ± 14 BP (IntCal20).
Selected curve values (14C BP): 450 BC: 2408, 400 BC: 2346, 350 BC: 2207, 300 BC: 2209, 250 BC: 2227, 218 BC: 2216, 200 BC: 2174, 150 BC: 2111, 100 BC: 2097, 50 BC: 2066, AD 1: 2030