First Antarctic Drilling 19721975

The period following World War II was marked by an expansion in both the scientific exploration of the oceans and the search for oil on the world's continental shelves. Echo-sounding techniques developed in war time were applied to marine seismic surveys for science and industry, and ship-based drilling for oil offshore attracted the attention of scientists for drilling through the Earth's crust. By the mid-1960s, the main features and gross chronology of most of the world's continental shelves...

Constraining Late Quaternary Ice Sheet Extent Volume and Timing

The geometry of the Antarctic Ice Sheet throughout the last glacial cycle has been compiled using a number of different methods. In terrestrial environments, the aerial extent of former ice cover is generally recognised by mapping the lateral extent of ice marginal landforms such as moraines or ice marginal lake sediments, or by mapping subglacial landforms such as drumlins and striae. Ice volume can equally be reconstructed by mapping glacial debris striae, the locations of erratic boulders...

Open Problems and Potential Research Themes for Future Geoscience Investigations in Antarctica

In contrast to all other continents, 99 of Antarctica (including its rocks and geological structures) is covered by a major ice sheet. Less than 1 of the continent provides our geological knowledge and even this has not been investigated thoroughly in all places. On the other hand, about half of the covered area has been surveyed geophysically, through mainly aeromagnetic and gravimetric techniques. Therefore, further investigations are needed and the image of the Antarctic geological structure...

Oceanographic Variability and Change

The present phase of climate change has drawn considerable attention to the behaviour of Antarctica and the Southern Ocean (e.g. Gille, 2002 Jacobs et al., 2002 Walther et al., 2002 Cook et al., 2005). However, confident identification of any effect, especially in the oceans, has been hindered by (i) sampling bias, (ii) the short history of observations, which typically only encompass the last 50-60 years, (iii) a multiplicity of forcing mechanisms, some with and some without clear connections...

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,...