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RESEARCH PRODUCT
Sea ice extent and seasonality for the Early Pliocene northern Weddell Sea
Victoria L PeckAndrew L. A. JohnsonJohn L. SmellieJohn L. SmellieAlan M. HaywoodAnna E. NelsonDaniel R. JarramBernd R. SchöneMelanie J. LengCarys E. BennettMark WilliamsMark WilliamsJan Zalasiewiczsubject
Drift iceWeddell Sea Bottom Watergeographygeography.geographical_feature_category010504 meteorology & atmospheric sciencesPaleontologyAntarctic sea ice010502 geochemistry & geophysicsOceanography01 natural sciencesArctic ice packOceanographyInterglacialSea iceCryosphere14. Life underwaterIce sheetEcology Evolution Behavior and SystematicsGeology0105 earth and related environmental sciencesEarth-Surface Processesdescription
Abstract Growth increment analysis coupled with stable isotopic data ( δ 18 O/ δ 13 C) from Early Pliocene (ca 4.7 Ma) Austrochlamys anderssoni from shallow marine sediments of the Cockburn Island Formation, northern Antarctic Peninsula, suggest these bivalves grew through much of the year, even during the coldest parts of winter recorded in the shells. The high frequency fluctuation in growth increment width of A. anderssoni appears to reflect periodic, but year-round, agitation of the water column enhancing benthic food supply from organic detritus. This suggests that Austrochlamys favoured waters that were largely sea ice free. Our data support interpretation of the Cockburn Island Formation as an interglacial marine deposit and the previous hypothesis that Austrochlamys retreated from the Antarctic as sea ice extent expanded, this transition occurring during climate cooling in the Late Pliocene.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2010-06-01 |