Table 1. Volcanic destruction layer radiocarbon determinations calibrated to IntCal13 and ICCP17.

Using OxCal 4.3, we compare results for a number of previously published modeling scenarios. Models 1 to 3 show different modeled approaches to the assemblage of annual materials from pre-eruption contexts on Akrotiri (8, 9, 15, 41). Models 4 and 5 show different modeled approaches for the Santorini olive branch, with assumptions of annual growth (10); annual growth with counting uncertainties of 25 and 50% (10); or an ordered sequence of unknown years, which moves from older to younger (13). All values for the olive branch represent posterior estimates of the outermost ring except model 7 (a simple ordered sequence), where the value relates to the estimated age of the outermost measurement.

Sample	Published model justification	Posterior mean cal BCE (2σ/95% credible interval)
		IntCal13	ICCP17
Akrotiri seed assemblage	1: Archaeological assemblage represents a phase (number of different years) before the eruption (Tau boundary function) (9, 15)	1625 (1646–1606)	1581 (1619–1536)
Akrotiri seed assemblage	2: Selected archaeological assemblage represents the same year before the eruption (adjusted for volcanic context, 3326 ± 11 14C B.P.) (41)	1608 (1658–1535)	1576 (1614–1539)
Akrotiri seed assemblage	3: Selected archaeological assemblage represents the same year before the eruption (unadjusted, 3345 ± 9 14C B.P.) (41)	1637 (1664–1614)	1587 (1664–1541)
Olive branch segments	4: Accepts olive increments as measured by Friedrich et al. (10) are annual	1615 (1626–1605)	1589 (1610–1567)
Olive branch segments	5: Ring count is increased by 25%, and gap uncertainty set to 25% of section count (10)	1611 (1627–1596)	1574 (1608–1511)
Olive branch segments	6: Gap uncertainty set to 50% of the ring count (10)	1622 (1721–1597)	1577 (1612–1528)
Olive branch segments	7: Treats sequence of olive segments as ordered but with no information on ring counts/gaps (13)	1614 (1642–1559)	1570 (1614–1538)