Deglacial seasonal and sub-seasonal diatom record from Palmer Deep, Antarctica.

• Published in: Journal of Quaternary Science
• Main Authors: Maddison, E.J., Pike, J., Leventer, A., Domack, E.W.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: John Wiley 2005
• Subjects: Antarctic Peninsula; Diatoms; Laminated sediments; Palaeoceanography; Palmer Deep; Antarctic; Austral; The Antarctic; Antarc*; Antarctica
• Online Access: http://dro.dur.ac.uk/7451/; https://doi.org/10.1002/jqs.947

The Antarctic Peninsula is one of the most sensitive regions of Antarctica to climate change. Here, ecological and cryospheric systems respond rapidly to climate fluctuations. A 4.4 m thick laminated diatom ooze deposited during the last deglaciation is examined from a marine sediment core (ODP Site 1098) recovered from Basin 1, Palmer Deep, western Antarctic Peninsula. This deglacial laminated interval was deposited directly over a glaciomarine diamict, hence during a globally recognised period of rapid climate change. The ultra-high-resolution deglacial record is analysed using SEM backscattered electron imagery and secondary electron imagery. Laminated to thinly bedded orange-brown diatom ooze (near monogeneric Hyalochaete Chaetoceros spp. resting spores) alternates with blue-grey terrigenous sediments (open water diatom species). These discrete laminae are interpreted as austral spring and summer signals respectively, with negligible winter deposition. Sub-seasonal sub-laminae are observed repeatedly through the summer laminae, suggesting variations in shelf waters throughout the summer. Tidal cycles, high storm intensities and/or intrusion of Circumpolar Deep Water onto the continental shelf introduced conditions which enhanced specific species productivity through the season.