| Depth (cm) | Unit Name | Description* | Notes |
|---|---|---|---|
| 0–19 | C | 2.5Y5/2 (grayish brown), very fine sand, loose sharp convoluted lower contact | Liquefaction deposits–sand blow |
| 19–37 | Ah | 10YR 3/2 (very dark grayish brown), peaty sandy loam, friable; soil—weak coarse blocky structure, fibrous in places with meter high organic matter content, abrupt, smooth (wavy in places) lower boundary | |
| 37–49 | 2C(f) | 2.5Y6/2 (light brownish gray) to 7.5YR 5/8 (strong brown), color ranges from 80/20% to 50/50% in different parts of unit; very fine sand, loose, millimeter-scale laminae, small concentrations of silt along laminae, sharp smooth wavy boundary | |
| 49–84 | 3C | 2.5Y 5/1 (gray) with common coarse faint 2.5 Y6/3 (brownish gray) mottles, loamy very fine sand sharp wavy lower contact, friable; soil—massive, centimeter-scale beds of millimeter-scale laminae of organic-rich material (laminae get truncated toward middle of trench by overlying sand unit), sharp wavy boundary | Detritus seems deposited in flowing water; soft sediment deformation apparent in units 3C and 4O/Cg; flame structures originated in 4O/Cg and continues into 3C |
| 84–112 | 4O/Cg | 2.5Y5/2 (grayish brown) with common distinct 7.5 YR 4/6 (strong brown) linear mottles vertically aligned (following root voids), mottles become semicontinuous across lower contact, very fine sand to loamy very fine sand to peaty loamy fine sand; structure—millimeter-to-centimeter scale laminations of peat (10YR 4/1—dark gray) toward the base organic horizon thicken to 5 cm containing wood, detrital organic matter, sharp wavy, and erosional lower contact | |
| 112–130+ | 4Cr | 2.5Y5/1 (gray) with common coarse prominent 7.5YR4/6 (strong brown) mottles vertically aligned oriented around root voids, loamy silt, slightly plastic nonsticky, slightly firm; soil—moderate medium prismatic structure, 2–10 mm pieces of detrital charcoal; contains a lens, 4Cr (organic), of more 7.5 YR 4/1 (dark gray) humic loamy silt, clear broken lower boundary | 4Cr (organic) is located between 2.2 and 2.8 m vertical on east wall |
| C′2 | 2.5 Y 4/2 (dark grayish brown), fine medium sand, loose massive, sharp wavy contact | Liquefaction deposits–sill | |
| C′1 | 2.5 Y 4/2 (dark grayish brown), fine sand grading upward to 2.5 Y 6/3 (yellowish brown) silt, silt appears as a 2–10-mm thick laminae at upper contact, clear wavy contact | Liquefaction deposits–sill |
* Soil description at 2.5 m vertical on west wall.
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