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Table 1 Field characteristics of the pre-Historical Holocene explosive eruption deposits

From: Challenges of determining frequency and magnitudes of explosive eruptions even with an unprecedented stratigraphy

Unit Eruption Age (yrs BP) Number of localities Thickness (cm) Max. Pumice (cm) Max. lithic (cm) Description
Z 360 ± 60–4240 ± 110 24 30 - > 200 Massive ash layer – series surge and ash fall deposits
Y 4460 ± 40 27 48–140 17 7 Tephra fall
X 4380 ± 80–4520 ± 60 19 2–12 Ash-rich surge
W 4480 ± 60–4540 ± 60 23 8–28 6 5 Tephra fall
V 4540 ± 60–4640 ± 60 25 2–15 Ash-rich surge
U 4740 ± 40–4790 ± 100 27 15–20 4 2 Tephra fall
T 4810 ± 50–5390 ± 50 26 5–100 3 subunits comprising tephra fall bounded by surge
S 5430 ± 50–5500 ± 60 22 12–46 4.5 2 2–3 fall deposits interbedded with PDC
R 5550 ± 80–5790 ± 50 21 2–29 Ash-rich surge
Q 5850 ± 60–5980 ± 50 18 25–50 2 tephra fall deposits separated by surge
P 5980 ± 50–6150 ± 40 20 6–42 9 6 Tephra fall
O 6150 ± 40–6950 ± 50 20 30 - > 100 Massive ash layer – series surge and ash fall deposits
N 6950 ± 50–7070 ± 60 16 12–60 17 12 Tephra fall
M 7070 ± 60–7520 ± 50 15 12–100 Ash-rich deposit with lenses of tephra fall
L 7520 ± 50–7530 ± 80 16 4–50 6 3 Tephra fall
K 7530 ± 80–7710 ± 60 10 38 - > 100 Series discontinuous interbedded PDC and fall
J 7750 ± 60–7760 ± 50 8 7–15 6 3 Tephra fall
H 9770 ± 60–10,310 ± 50 9 15–42 5 2 Tephra fall
F 11,840 ± 70–12,080 ± 150 6 3–90 5 8 Tephra fall
D 12,460 ± 60–13,350 ± 130 9 32–180 6.5 5 Tephra fall
  1. The five best-exposed and correlated units modelled here are in bold. Ages are uncalibrated radiocarbon dates from Luhr et al., 2010