Holocene Oceanographic and Climatic Variability of the Vega Drift Revealed Through Foraminiferal Interpretation -Online Proceedings of the 10 th ISAEC

• Main Authors: U S Szymcek, P, S E Ishman, E W Domack, A Leventer
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Antarctic Peninsula; Prince Gustav Channel; Antarc*; Antarctica; Neogloboquadrina pachyderma
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1090.1197

Abstract A sediment sequence recovered from the Vega Drift, Antarctica was analyzed for benthic foraminifera to determine Holocene oceanographic and climatic variability of the northern Antarctic Peninsula margin. Core NBP0003-JPC38, collected during cruise 00-03 of the R.V. Nathaniel B. Palmer recovered 20.53 meters of Holocene glacio-marine sediments. Samples were collected every 4 cm for foraminiferal analyses. The data were analyzed using principal component and cluster analyses. Results of these analyses show significant stratigraphic changes in the benthic foraminiferal record of the Vega Drift. Three assemblages characterize the core, including the Miliammina arenacea, Textularia wiesneri, and Stainforthia fusiformis assemblages. Most agglutinated forms tend to decrease downcore, and comparisons to modern analogues imply post-depositional disintegration, while calcareous taxa indicate non-corrosive bottom waters. The lower to middle Holocene Vega Drift sediments are characterized by the calcareous S. fusiformis assemblage and glacial plume sediments. This assemblage is characterized by calcareous forms including Globocassidulina biora, G. subglobosa, and Nonionella iridea. The planktic species Neogloboquadrina pachyderma is associated with the S. fusiformis assemblage. The S. fusiformis assemblage is faunally similar to assemblages described in fjords of the western Antarctic Peninsula and indicates non-corrosive bottom water. Sediments of the mid to upper Holocene interval are characterized by the T. wiesneri and M. arenacea assemblages and indicate the presence of Hyper Saline Shelf Water. These assemblages are similar to modern assemblages directly to the south in the Prince Gustav Channel. The upper Holocene is marked by several small intervals with taxonomic characteristics similar to the S. fusiformis assemblage, indicating periodic introduction of non-corrosive bottom water to the Vega Drift.