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In 1987 C. McA. Powell and J. J. Veevers postulated that the mid-Carboniferous uplift of the Centralian fold-and-thrust belt led to the growth of an ice sheet that covered much of Australia as it drifted from low to high latitudes. They presumed that the voluminous sediment shed from the final disruption and stripping to basement of the Centralian Superbasin was transported by ice streams out of the foreland basin to the edge of the ice sheet in the eastern and west-northwestern margins. Geochronological data accrued since 1987 confirm the 330-320 Ma synchronicity of uplift and exhumation in Centralia, deposition of glacial sediment on the margins and the onset of glacio-eustasy, as indicated by cyclothemic sedimentation patterns in the Visean platform carbonates of the British Isles. These events are by-products of the 330-320 Ma merging of Gondwanaland and Laurussia in Pangaea that provided the global setting for glaciation. Probably more influential in initiating glaciation was the greater uplift in the Gamburtsev Subglacial Mountains of East Antarctica that became the focus of Permian post-glacial dispersal of sediment in East Gondwanaland. [ABSTRACT FROM AUTHOR]

There is growing consensus that development of a semipermanent ice sheet on Antarctica began at or near the Eocene-Oligocene (E-O) boundary. Beyond ice-rafted debris in oceanic settings, however, direct evidence for a substantial ice sheet at this time has been limited and thus far restricted to East Antarctica. It is unclear where glacier ice first accumulated and how extensive it was on the Antarctic continent in the earliest Oligocene. Sediments at the top of the Eocene marine shelf section on Seymour Island, Antarctic Peninsula, include glacial marine deposits and a lodgment till with clasts derived from a variety of rock units on the peninsula. Dinoflagellate biostratigraphy and strontium isotope stratigraphy indicate an age at or very close to the E-O boundary. Glacier ice extending to sea level in the northern peninsula at this time suggests the presence of a regionally extensive West Antarctica ice sheet, and thus an even more dramatic response to the forcing factors that facilitated high-latitude ice expansion in the earliest Oligocene. [ABSTRACT FROM AUTHOR]