Environmental connotations of benthic foraminiferal assemblages from coastal West Antarctica

• eight FAs reflect large variability in benthic foraminiferal assemblages and environments in West Antarctic coastal settings
• six FAs are dominated by calcareous taxa may be arranged according to decreasing glacial influence
• two FAs are dominated by arenaceous taxa, indicating corrosive conditions
• variable food supply and its seasonal delivery is the most important factor impacting FAs
• three FAs (B. aculeata, Epistominella spp., and Portatrochammina spp., FAs) occur where Circumpolar Deep Water impinge onto the continental shelf

This paper examines the variability in foraminiferal assemblages in surface samples from coastal settings along the northwestern Antarctic Peninsula, as well as in the Pine Island Bay area. Material comes from water-depths ranging between 20 and 1257 m, latitudes between 62° and 73°S, and bottom water temperatures from − 1.5 to 1.2 °C. The microfossil analysis within this broad geographical and environmental context provides a basis for paleo-environmental studies. Environmental affinities of the assemblages were interpreted based on a wide array of ecological conditions, including CTD data, as well as on faunal indices and ecological affinities of the key taxa. Six foraminiferal assemblages are dominated by calcareous taxa. Among other factors, they correspond to variable food supply, terrigenous sedimentation, and water mass properties. Another two assemblages are dominated by arenaceous foraminifera and reflect conditions corrosive to carbonate. Our findings indicate that preserved fossil assemblages in cores from these locations may not be accurate representations of living assemblages.