Sedimentological, geochemical and palaeontological evidence for a neoglacial cold event during the late Holocene in the continental shelf of the northern South Shetland Islands, West Antarctica

Polar research

Boo-Keun Khim¹  Jin-Kyung Kim²  Ho Il Yoon³  Kyu-Cheul Yoo⁴ 

[1] Division of Earth Environmental System, Pusan National University, Busan 609-735, Korea;Korea Polar Research Institute, Songdo Techno Park, 7-50, Inchon, Korea;Korea Polar Research Institute, Songdo Techno Park, 7-50, Inchon, KoreaCorrespondence;School of Earth and Environmental Sciences, Seoul National University, Seoul 151-747, Korea

关键词: Antarctic Peninsula;    continental shelf;    diatom assemblages;    gravity core;    Little Ice Age;    recent warming.;   

DOI  :  10.1111/j.1751-8369.2009.00109.x

学科分类：自然科学（综合）

来源: Co-Action Publishing

【 摘 要 】

Two sediment cores obtained from the continental shelf of the northern South Shetland Islands, West Antarctica, consist of: an upper unit of silty mud, bioturbated by a sluggish current, and a lower unit of well-sorted, laminated silty mud, attributed to an intensified Polar Slope Current. Geochemical and accelerator mass spectrometry 14C analyses yielded evidence for a late Holocene increase in sea-ice extent and a decrease in phytoplankton productivity, inferred from a reduction in the total organic carbon content and higher C : N ratios, at approximately 330 years B.P., corresponding to the Little Ice Age. Prior to this, the shelf experienced warmer marine conditions, with greater phytoplankton productivity, inferred from a higher organic carbon content and C : N ratios in the lower unit. The reduced abundance of Weddell Sea ice-edge bloom species (Chaetoceros resting spores, Fragilariopsis curta and Fragilariopsis cylindrus) and stratified cold-water species (Rhizosolenia antennata) in the upper unit ...

【 授权许可】

CC BY-NC