Glacial-interglacial records from sediments in Powell Basin, Antarctica

Abstract

Palaeoenvironmental history is reconstructed from diatoms in two sediment cores, GC01-PW02 and GC03-PW02, recovered from Powell Basin, Antarctica. A total of 43 species belonging to 21 genera are identified from GC01-PW02. A total of 61 species belonging to 27 genera are identified from GC03-PW02. The number of diatom valves g-1 of dry sediment ranges from 0.1？48.3 ×106 valves g-1. Based on diatom abundance, six assemblage zones were identified from GC01-PW02, and five diatom zones were identified from GC03-PW02. Barren intervals represent glacial periods, while intervals with higher diatom abundances were deposited during interglacial periods and reduced sea ice cover. The occurrence of Rouxia leventerae only within the deepest zone of each of the cores indicates that the core sediments were deposited since marine isotope stage (MIS) 6.