Table 2 Description of sandy event deposits in samples SKN-W, SKN-E, and SKN-GS
Location | Event no. | Grain size | Thickness (cm) | Sedimentary structure | Interpretation |
|---|---|---|---|---|---|
SKN-E | E1 | fs, ms | 5 | Â | Â |
| Â | E2 | fs, ms | 3 | Â | Â |
| Â | E3 | fs, ms | 3 | Â | Â |
| Â | E4 | fs, ms | 3 | Normal grading | Â |
|  | E5 | ms-granule | 10–15 | Normal grading, rip-up clasts (< 1 cm), pumice clast (< 1 cm), gravel (2–3 cm) at lower part, erosive contact at base |  |
|  | E6 | ms-granule | 3–15 | Normal grading, rip-up clasts, gravel (3 cm), erosive contact at base |  |
|  | E7 | ms, cs | 25–30 | Channel fill, erosion up to E10, parallel laminae |  |
|  | E8 | ms-vcs | 5–10 | Patchy distribution, normal grading, rip-up clasts |  |
|  | U-2 (drift pumice) |  |  |  | U-2 (5681–5619 cal yr BP) |
|  | E9 | ms-granule | 3–5 | Poor sorting |  |
| Â | To-Cu (drift pumice) | Â | Â | Â | Â |
|  | To-Cu (fallout ash) |  |  |  | To-Cu (5986–5899 cal yr BP) |
| Â | E10 | ms | 3 | Patchy distribution | Â |
|  | E11 | silt, ms-cs | 10–20 | Matrix rich, a little grading, bioturbation |  |
| Â | E12 | fs, silt | Â | Matrix rich, patchy distribution | Â |
SKN-W | E1 | ms, cs |  > 16 | Parallel laminae in the lower part |  |
| Â | E2 | ms, cs | 4 | Â | Â |
|  | E3 | ms | 6–9 |  |  |
| Â | E4 | Ms | 12 | Erosive contact at base | Â |
|  | E5 | ms | 5–10 |  |  |
| Â | B-Tm | fs | 2 | Normal grading | B-Tm (946 CE) |
| Â | E6 | fs | 5 | Â | Â |
|  | E7 | fs, ms | 5–8 |  |  |
|  | E8 | fs | 6–20 | Parallel laminae |  |
|  | E9 | fs, ms | 2–4 |  |  |
|  | E10 | fs, ms | 4–8 | Erosive contact at base |  |
|  | E11 | ms, cs | 6–7 | Normal grading, erosive contact at base |  |
|  | E12 | ms | 1–5 |  |  |
| Â | E13 | ms | 3 | Â | Â |
|  | E14 | ms, cs | 5–9 | Normal grading, erosive contact at base |  |
|  | E15 | fs | 1–2 | Not continuous |  |
|  | E16 | ms | 7–12 | Normal grading |  |
|  | E17 | ms | 4–10 |  |  |
SKN-GS | GS9-E1 | ms | 10 | Composed of 2–3 units, erosive contact at base |  |
| Â | Volcanic ash | fs | 3 | Â | B-Tm (946 CE) |
|  | GS9-E2 | fs, ms | 2–3 | Erosive contact at base |  |
| Â | GS9-E3 | ms | 6 | Erosive contact at base | Â |
| Â | GS9-E4 | ms | 4 | Unclear | Â |
|  | GS8-E1 | ms | 13 | Composed of 2–3 units, erosive contact at base |  |
| Â | Volcanic ash | fs | 3 | Â | B-Tm (946 CE) |
| Â | Volcanic ash | fs | 2 | Laminae | B-Tm (946 CE) |
| Â | GS8-E2 | ms | 2 | Erosive contact at base | Â |
| Â | GS8-E3 | ms, cs | 5 | Laminae, erosive contact at base | Â |
| Â | GS8-E4 | silt-granule | 36 | Erosive contact at base | Â |
| Â | GS8-E5 | fs, ms | 3 | Unclear laminae, erosive contact at base | Â |
|  | GS8-E6 | fs, ms | > 3 | Parallel laminae |  |
|  | GS1-E1 | fs, ms | 15 | Composed of 2–3 units, erosive contact at base |  |
| Â | Volcanic ash | vfs | 4 | Â | B-Tm (946 CE) |
| Â | GS1-E2 | ms | 3 | Unclear laminae, erosive contact at base | Â |
|  | GS1-E3 | ms | 9 | Cross laminae, laminae tilting to inland, erosive contact at base |  |
|  | GS1-E4 | ms-granule | 52 | Parallel laminae, cross laminae, laminae tilting to seaward, fining upward in the upper part, coarsening upward in the lower part, erosive contact at base |  |
| Â | GS1-E5 | fs | 3 | Â | Â |
| Â | GS1-E6 | fs | 1 | Â | Â |
|  | GS7-E1 | ms | 13 | Composed of 2–3 units, erosive contact at base |  |
|  | Volcanic ash | fs | < 1 | Patchy distribution | B-Tm (946 CE) |
| Â | GS7-E2 | fs | 1 | Unclear, identified in XCT image | Â |
|  | GS7-E3 | ms-granule | 45 | Parallel laminae, cross laminae, laminae tilting to seaward, fining upward in the upper part |  |
|  | GS7-E4 | ms, cs | > 5 |  |  |
|  | GS6-E1 | ms | 12 | Composed of 2–3 units, erosive contact at base |  |
|  | Volcanic ash | fs | 2–3 |  | B-Tm (946 CE) |
| Â | GS6-E2 | ms, cs | 1 | Erosive contact at base | Â |
|  | GS6-E3 | ms, cs | 8 | Cross laminae, laminae tilting to inland, normal grading, erosive contact at base |  |
| Â | GS6-E4 | ms | 1 | Erosive contact at base | Â |
| Â | GS6-E5 | vcs | 12 | Erosive contact at base | Â |
|  | GS6-E6 | ms, cs | 5 | Cross laminae, laminae tilting to inland, erosive contact at base |  |
| Â | GS6-E7 | vcs, granule | 3 | Contain rounded gravel, erosive contact at base | Â |
| Â | GS5-E1 | ms, fs | 1 | Â | Â |
| Â | GS5-E2 | ms, fs | 7 | Erosive contact at base | Â |
|  | GS5-E3 | csms | 15 | Composed of 2–3 units |  |
| Â | GS5-E4 | ms-granule | 5 | Contain rounded gravel, normal grading, erosive contact at base | Â |
| Â | GS5-E5 | ms-vcs | 6 | Inversegrading, unclear laminae, erosive contact at base | Â |
| Â | GS5-E6 | ms | 4 | Erosive contact at base | Â |
| Â | GS4-E1 | ms, fs | 1 | Patchy distribution | Â |
| Â | GS4-E2 | ms, fs | 3 | Composed of 2 units | Â |
| Â | GS4-E3 | ms, fs | 1 | Patchy distribution | Â |
| Â | GS4-E4 | fs | 5 | Unclear, identified in XCT image | Â |
|  | GS4-E5 | ms, cs | 18 | Composed of 2–3 units |  |
| Â | GS4-E6 | fs-granule | 53 | Composed of multiple units, fining upward in the upper part, coarsening upward in the lower part, erosive contact at base | Â |
| Â | GS3-E1 | ms | 6 | Patchy distribution | Â |
| Â | Volcanic ash | fs | 10 | Unclear, identified in XCT image | B-Tm (946 CE) |
| Â | GS3-E2 | fs | 2 | Unclear, identified in XCT image | Â |
| Â | GS3-E3 | ms | 1 | Â | Â |
| Â | GS2-E1 | fs, ms | 10 | Unclear, identified in XCT image | Â |
| Â | Volcanic ash | fs | 5 | Â | B-Tm (946 CE) |
| Â | GS2-E2 | fs, ms | 1 | Erosive contact at base | Â |
| Â | GS2-E3 | fs, ms | 10 | Erosive contact at base | Â |
| Â | GS2-E4 | fs, ms | 10 | Erosive contact at base | Â |
| Â | GS2-E5 | fs, ms | 3 | Unclear parallel laminae, erosive contact at base | Â |