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{"Abstract":["This dataset consists of detrital zircon U-Pb data from samples from the Amundsen Sea Embayment. The data are a product of the publication: "Reconstructing Eocene Antarctic river drainage from provenance analysis of Amundsen Sea Embayment sediments".\n\nIncluded are data from three Holocene sediment samples strategically located around the embayment to help characterise the detritus currently being eroded and deposited in the Amundsen Sea. Samples comprise of locations proximal to Pine Island Glacier and Thwaites Glacier, with a further sample to the north of Thwaites Glacier. A fourth sample consists of Cretaceous mudstone from a drill core from site PS104_20-2 in the Amundsen Sea Embayment.\n\nA second file contains a compilation of selected detrital zircon U-Pb dates from potential source areas around West Antarctica. These include the sedimentary rocks of the Swanson Formation and Ellsworth-Whitmore Mountains, as well as all published West Antarctic subglacial till data. Data from moraines in the Transantarctic Mountains are also included."]}
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Reconstructing Eocene Antarctic river drainage from provenance analysis of Amundsen Sea embayment sediments
Sedimentary records can illuminate relationships between the climate, topography, and glaciation of West Antarctica by revealing its Cenozoic topographic and paleoenvironmental history. Eocene fluvial drainage patterns have previously been inferred using geochemical provenance data from an ~44– to 34–million year deltaic sandstone recovered from the Amundsen Sea Embayment. One interpretation holds that a low-relief, low-lying West Antarctic landscape supported a >1500-kilometer transcontinental river system. Alternatively, higher-relief topography in central West Antarctica formed a drainage divide between the Ross and Amundsen seas. Here, zircon U-Pb data from Amundsen Sea Embayment sediments are examined alongside known regional bedrock provenance signatures. These analyses suggest that all observed provenance indicators in the Eocene sandstone derive from West Antarctic rocks. This implies that a local river system flowed off a West Antarctic drainage divide, helping constrain the mid-Late Eocene evolution of West Antarctic topography with implications for the history of rifting and the characteristics of sediments infilling interior basins.
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- Award ID(s):
- 1917176
- PAR ID:
- 10654903
- Publisher / Repository:
- AAAS Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 11
- Issue:
- 50
- ISSN:
- 2375-2548
- Subject(s) / Keyword(s):
- Eocene paleotopography West Antarctica fluvial system subglacial geology sediment provenance
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1126/sciadv.aea2373
