The South Shetland Islands Region

This subregion includes the Bransfield Strait and the continental margin around the South Shetland Islands (Fig. AP-1). Bransfield Strait is a 2,000 m deep rift basin that is actively extending at 7mm y. (Dietrich et al., 2004). The time of initial extension and the oldest age of basin sediments are uncertain, but may be 4 Ma (Barker and Dalziel, 1983) or 6Ma (Larter and Barker, 1991a). Gamboa and Maldonado (1990) speculate that Bransfield Strait may have opened earlier, during the early...

Tectonic Evolution and Magmatism in the Ross Sea Sector during the Cenozoic

With a similar form to the Weddell Sea, the Ross embayment is one of the most striking morphological expressions of the WARS, a region of thin, and, by inference, extended continental crust whose regional boundaries are difficult to define precisely and may have been different for different episodes of extension (Fig. 7.5). Three major episodes of extension have been proposed, with rifting starting in the Middle Jurassic, in coincidence with the onset of Gondwana break-up and the associated...

Marie Byrd Land

Marie Byrd Land contains the largest Cenozoic volcanic field in Antarctica (LeMasurier and Thomson, 1990). It is also the most remote region and is among the least visited and least well known of all Antarctic volcanoes. Numerous reports published in the 1970s and 1980s suggested a subglacial origin for many centres (summarized by LeMasurier and Rocchi, 2005). While agreeing generally that the eruptive environment was probably glacial, the published criteria used most often (e.g. mainly...

The First International Polar Year 18821883

In August 1874, Captain Karl Weyprecht (1838-1881) (Figs. 2.1 and 2.2) returned from an Arctic expedition, of which he was leader. The Figure 2.1 Carl Weyprecht (1838-1881) ideas initiated the first IPY (photo courtesy Archive, Alfred Wegener Institute for Polar and Marine Research). Figure 2.1 Carl Weyprecht (1838-1881) ideas initiated the first IPY (photo courtesy Archive, Alfred Wegener Institute for Polar and Marine Research). Austro-Hungarian North Pole Expedition (1871-1874) aimed to...

The Third International Polar Year International Geophysical Year 19571958

Lawrence Donnell Young

Following the success of the first two polar years it seemed reasonable to agree that these events should occur every 50 years. However, so many scientific and technological improvements were made in a short time after the second IPY that already at the beginning of the fifties many scientists believed a third coordinated IPY would allow major advances in our knowledge of Antarctica, which should not wait until the 50th anniversary of the second IPY. On 5 April 1950, in Silver Spring, Maryland,...