Database dump for this sample: |
| Top depth (cm) | 17.0 |
| Bottom depth (cm) | 18.0 |
| Lithology | Bioturbated diatom ooze with abundant clasts (DO). High opal (20-25 percent), TOC content (>0.5 percent), and high water content (around 40- 50 percent). Clasts include: Granite, rounded quartz, quartz, feldspars, dolerite, foliated/mylontic granitoids, basalt. High diatom abundance (1.4 * 10^9 valves/g). Benthic forams present. |
| Facies interpretation | Pelagic sedimentation with ice rafted debris. General lack of terrigenous material. Thin bioturbated interval with abundant clasts suggests winnowing and current reworking (Domack et al., 1999) and is likely a condensed section. At the time of coring the site was 15 km south of the calving line, but was ~5km from the calving line when C-19 (a 200x32 km iceberg) calved off in 2002. This effectively places the CH-2 in the modern day 'calving zone' of the Ross Ice Shelf since the ice shelf became pinned to Ross Island during the glacial retreat. The presence of gravel clasts indicates open water with ice rafting must have existed at numerous time through the Holocene, as the base of the Ross Ice Shelf at this site was observed by video observations during hot water drilling to be free of basal debris. |
| Core sample comments | None |
| Carbon type | AIO |
| Analysis date | None |
| Chem lab | None |
| Analyst | None |
| Sample preparation method | None |
| AMS lab | Rafter Radiocarbon Lab |
| AMS date | None |
| Analysis ID | NZA37625 |
| Percent carbon | None |
| Fraction modern | None |
| δ13C (‰) | None |
| 14C age (yr) | 16018.0 |
| 14C age uncertainty (yr) | 55.0 |
| 14C comments | None |
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Calibration results: |
| Calibration curve | Marine20 |
| Reservoir correction (14C yr BP) (mean and st.dev. of all Antarctica calibration samples) (http://calib.org/marine/) | 1141 ± 179 |
| Calibration software | IOSACal (v.0.6.0) |
| Calibrated age 95.45 % HPD interval(s) (yr) | 17743.0 to 16682.0 cal yr BP |
| Calibrated age 68.2 % HPD interval(s) (yr) | 17429.0 to 16923.0 cal yr BP |
| 14C calibration plot | |
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