Diatom biostratigraphy and age of the Pliocene Sørsdal Formation, Vestfold Hills, East Antarctica

• Published in: Antarctic Science
• Main Authors: Harwood, David M., McMinn, Andrew, Quilty, Patrick G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2000
• Subjects: Southern Ocean; East Antarctica; Ross Sea; Vestfold Hills; Vestfold; Marine Plain; Antarc*; Antarctic Science; Antarctica; Sea ice
• Online Access: https://doi.org/10.1017/s0954102000000535; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102000000535

Fossil marine diatom assemblages from the Sørsdal Formation, a deposit of diatomaceous sand from Marine Plain in the Vestfold Hills, provide age and palaeoenvironmental information from a Pliocene coastal setting in East Antarctica. Benthic and meroplanktic diatom taxa suggest deposition in a shallow coastal embayment with water depths of 20–25 m. Diatom biostratigraphy indicates that the Sørsdal Formation belongs to the Fragilariopsis barronii Zone (4.5 to 4.1 Ma), through correlation to reference sections in the Ross Sea and Southern Ocean. Features of the other biota suggest higher sea-surface temperatures and reduced sea-ice cover, consistent with global records of higher sea level.