Late Quaternary climatic changes around the Elephant Islands, Antarctic Peninsula

Abstract

Sixty-seven species of diatoms of 28 genera were identified in Core GC03-C2 acquired from the north slope of Elephant Island, Antarctic Peninsula. The number of diatom valves per gram of dry sediment ranged from 0.2~17.3 × 10⁷g^-1, and these were dominated by <em>Fragilariopsis kerguelensis</em> (65.8%). Diatom assemblage analysis reconstructed the Quaternary paleoclimatic change the Elephant Islands. Four diatom assemblage zones were identified according to the frequency of critical taxa as follows: zone I, from 830 to 710 cm (Antarctic Cold Reversal); zone II, from 700 to 550 cm (Deglaciation zone); zone III, from 540 to 260 cm (warm period; Holocene); and zone IV, from 250 to 0 cm (cool period; Holocene). The high abundance of reworked species includes <em>Actinocyclus ingens, Denticulopsis hustedtii, D. praedimorpha,</em> and<em> D. dimorpha</em> appeared in Zone I by turbidity currents and ice rafting in the area during the glaciations-deglaciation event.