Late Quaternary record of sea-level changes in the Antarctic
The Late Quaternary sediment sequence of the continental margin in the eastern Weddell Sea is well suited for palaeoenvironmental reconstructions. Twocores rom the upper slope, which contain the sedimentary record of the last 300 ky, have been sedimentologically investigated. Age models are based on...
| Summary: | The Late Quaternary sediment sequence of the continental margin in the eastern Weddell Sea is well suited for palaeoenvironmental reconstructions. Twocores rom the upper slope, which contain the sedimentary record of the last 300 ky, have been sedimentologically investigated. Age models are based onlithostratigraphy and are correlated with the stable isotope record. As a result of a detailed analysis of the clay mineral composition, grain size distributionsand structures, this sedimentary record provides the first marine evidence that the Antarctic ice sheet extended to the shelf edge during the last glacial.The variations in volume and size of the ice sheet were also simulated in numerical models. Changes in accumulation rate and ice temperature are of someimportance, but the model revealed that fluctuations are primarily driven by changes in eustatic sea-level and that the ice edge extended to the shelf edgeduring the last glacial maximum. This causal relationship implies that the maximum ice extension strongly depends on the magnitude and duration of thesea-level depression during a glacial period. The results of sedimentological investigations and of the numerical models show that the Antarctic ice sheetfollows glacial events in the northern hemisphere by teleconnections of sea level. |
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