Late Paleogene and Early Neogene Foraminifers of Deep Sea Drilling Project Site 270, Ross Sea, Antarctica

Abstract

Foraminifers from the upper Oligocene, lower Miocene, and Pleistocene at Site 270 in the southern Ross Sea, Antarctica, are discussed and illustrated. The total fauna comprises 74 genera and 163 species. A small number of taxa are recycled from Cretaceous and older Paleogene sediments. Four assemblage zones are proposed, the age of informal lithologic units discussed, and potentially important hiatuses identified. Microfaunas reflect a mixing of biogeographic affinities with one element exhibiting similarities to temperate late Paleogene assemblages in New Zealand, and another representing the early cold-water assemblages of the antarctic Neogene.

Late Cenozoic Foraminifera from Diamictites of Cape Lamb, Vega Island, Antarctic Peninsula

“…6. Remarks. our specimen agrees with those illustrated by Anderson (1975) and Leckie and Webb (1986), with apiculate base.…”

“…2011), from Elphidium magellanicum s.l. heron-Allen and Earland illustrated by Leckie and Webb (1986) which was included by Quilty (2010) as a synonym of his species, and from Elphidium magellanicum illustrated by strong and Webb (2000, p. 469, pl. 1, figs.…”

Magnetostratigraphic Calibration of the Late Oligocene Climate Transition

“…In particular, if ice mass equivalent to the modern-day Antarctic ice disappeared at this time, it might strengthen the case for an unstable East Antarctic Ice Sheet; however, our data and those of Lear et al (2004) indicate that the late Oligocene δ 18 O decrease was much less than that reconstructed based on spliced records from different ocean basins (Zachos et al, 2001). Modest changes in Antarctic ice volume are more in line with evidence for persistent grounded ice in the Ross Sea during the late Oligocene (Hayes and Frakes, 1975;Leckie and Webb, 1986;DeSantis et al, 1995) and terrestrial evidence that indicates temperate climates throughout the late Oligocene (Askin, 1992).…”

“…This association has been found at Deep Sea Drilling Project (DSDP) Site 529 (Miller et al, 1991), whereas Oi2b is recorded in Chron 8r at Site 522 (Miller et al, 1988). This δ 18 O maximum may also correlate with glacial marine sequences in the Ross Sea (Leckie and Webb, 1986 (Fig. F5).…”

Neogene Benthic Foraminifers from the Southern Indian Ocean (Kerguelen Plateau): Biostratigraphy and Paleoecology

“…Investigations of benthic foraminifers from Neogene sections from south of the present-day Antarctic Convergence are from Rögl (1976), Leckie and Webb (1986) and Thomas (1990). I quantitatively examined benthic foraminifers from the Neogene sections of Leg 120 Sites 747, 748, and 751.…”