Ammoelphidiella from the Pliocene of Larsemann Hills, East Antarctica

Fossil proxies of near-shore sea surface temperatures and seasonality from the late Neogene Antarctic shelf

“…A. anderssoni in Williams et al (2010) or indirectly using species tolerances (e.g. dolphin fossils in Quilty et al (1990), suggest that there was a reduction in sea ice during warmer intervals. Though the temporal dataset is fragmentary, there does not seem to be significant evidence for temperature trends either towards a long-term cooling or warming through the Pliocene.…”

“…They consist of grey clayey sand that contains in situ fossiliferous material similar to that obtained in the Vestfold Hills (Quilty et al 1990). The Larsemann Hills deposits were originally dated as Pliocene using the age range of the foraminifer Ammoelphidiella antarctica (3.8-2.5 Ma; Webb 1974;Quilty et al 1990), though this was later revised to 4.5 to 3.8 Ma (McMinn and Harwood 1995).…”

“…and lacks planktonic foraminifer species, suggesting a shallow water, fully marine environment at or above wave base (Quilty et al 1990). The marine fossils found there are different from the modern faunas found in the region, likely due to its shallower origin (Quilty et al 1990).…”

“…and lacks planktonic foraminifer species, suggesting a shallow water, fully marine environment at or above wave base (Quilty et al 1990). The marine fossils found there are different from the modern faunas found in the region, likely due to its shallower origin (Quilty et al 1990). Assuming a similar age of deposition to Marine Plain (4.5-4.1 Ma), this suggests the area had less intense glaciation than at present (Pickard et al 1988) and was probably warmer with a higher sea level (Quilty et al 1990).…”

“…A number of proxies have converging temperature data; for example maximum temperatures of up to +5°C during the summer months have been calculated in deposits of overlapping ages (4.6 to 3.3 Ma) in Prydz Bay, the Vestfold Hills, Ross Sea and the western Antarctic Peninsula margin using silicoflagellates (Whitehead and Bohaty 2003;Escutia et al 2009), diatoms (Whitehead et al 2001;Scherer et al 2010), and vertebrates (Quilty et al 1990;Quilty 1991;Quilty 1993); see Table 4 for details. These same data also indicated a reduction in sea ice and open ocean conditions during the summer months.…”