Introduction

The geological literature has for a long time demonstrated the fundamental role of Antarctica as a key continent for providing data and constraints to supercontinent reconstructions and the plate tectonic evolution of the Southern Hemisphere. Du Toit's (1937) Gondwana reconstruction could be hypothesised on the basis of the results of the heroic period first expeditions (i.e. the Glossopteris-bearing Beacon sandstones collected during the last Scott's expedition). The Mesoproterozoic Rodinia supercontinent (Dalziel, 1991; Moores, 1991) provides another example with fundamental pieces of evidence linked to the central position envisaged for Antarctica with respect to the other continental blocks, albeit the configurations differ for the proposed supercontinent.

Progressively revealed by increased research activities of national and multinational expeditions following the 1957-1958 International Geophysical Year to those planned for the International Polar Year 2007/2008, the geological record of Antarctica has now a similarly valuable interest and importance in the context of palaeoenvironmental and palaeoclimatic investigations, particularly those focused on the initiation of Cenozoic glaciation, the stability of the polar ice sheets and the complex interaction among tectonic, sedimentary and climatic processes.

In the following sections, the Antarctic geological record is reviewed in the context of the major phases of the late Neoproterozoic-Cenozoic plate tectonic evolution of the Southern Hemisphere. The chapter describes the evolution of the Antarctic continent from its inclusion as part of the Gondwana supercontinent to the break-up of this landmass and the repositioning of Antarctica at southern polar latitudes since the Early Cretaceous (c. 120 Ma). The chapter also highlights some of the most interesting palaeoclimatic issues, which are considered essential to understanding the polar climate, ice ages and their influences on Earth's climate system throughout the Cenozoic.

The aim is to give a general overview which should be complementary to the more detailed information included in the accompanying chapters devoted to specific aspects of the geological record. Moreover, the review will highlight some of the main persisting open problems and those aspects of Antarctic tectonic evolution that are still not completely investigated or are under debate and may potentially be understood as major research themes for future on- and off-shore research.

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