Visual observations and stratigraphy of the South Pole Ice Core (SPICEcore) : a preliminary Holocene (~10.2 ka) accumulation record and depth-age chronology
Fegyveresi, John M.; Fudge, Tyler Jeffrey.; Ferris, David G.; Winski, Dominic A.; Alley, Richard B.
We present an initial chronology for the newly drilled South Pole Ice Core (SPICEcore). Annual layers observed in the visual stratigraphy of the upper 735 m indicate a total ice age chronology of 10,235 ± 51 BP (years be-fore 1950), with a total average accumulation rate of approximately 7.4 cm a⁻¹we. Comparing electrical conductivity measurement peaks in the core with known volcanic events observed in other Antarctic ice cores corroborates these estimates. This history shows accumulation trends, which could indicate past climatological or glaciological changes at the site. Specifically, one 1600-year interval between 6700 and 5100 years BP experienced a higher-than-average accumulation rate (~8.1 cm a⁻¹we) while one 700-year interval from 3100 to 2400 years BP experienced a lower-than-average accumulation rate (~6.4 cm a⁻¹we). We used seasonal equivalent coarse-grained and depth-hoar layers to identify the annual “picks” (noted as summers); and the stratigraphy in the core was generally uniform and well-preserved. We ob-served and documented over 1900 individual wind or iced crusts. We noted one visible tephra layer at a depth of 306.6 m in the core (~3560 years BP), which is likely tied to an eruption of Candlemas Island in the South Sandwich Islands.
Cold Regions Research and Engineering Laboratory (U.S.)Engineer Research and Development Center (U.S.)
Antarctic history; Climatic changes; Cyrospheric science; Glaciology; Ice core chronology; Ice core dating; Ice cores; Ice--Antarctica; Ice-sheet history; Polar science; Polar volcanic records; Snow accumulation; South Pole history; SPICEcore
Technical Report (Engineer Research and Development Center (U.S.)) ; no. ERDC/CRREL TR-19-10
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