The ice cover on the continent and in the surrounding ocean basins makes geological investigations in Antarctica very difficult. In addition, with the exception of the peninsula and glacial deposits, there are no sedimentary rocks on the Antarctic continent that are younger than Jurassic. Indirect methods must be used to obtain information about these periods that are not directly documented by geological evidence. Geological drilling projects are an important way of obtaining specific information about the geological development of these time periods. In the past, the BGR has been involved in two such research drilling projects: the Cape Roberts project, in which it was also a member of the steering committee, and its follow-up project ANDRILL. The BGR is currently involved in the New Zealand-led international drilling project ‘Sensitivity of the West Antarctic Ice Shield to 2°C of Warming’ (SWAIS2C) in the western Ross Sea. In addition, BGR and AWI are working together on the preparation of their own drilling proposal ‘Sub-Ekström Ice Shelf-Observation’ (Sub-EIS-Obs) on the Ekström Ice Shelf near the German wintering station Neumayer-III off Dronning Maud Land in East Antarctica.
Current and planned drillings
Sensitivity of the West Antarctic Ice Sheet to 2°C (SWAIS2C)
The BGR is significantly involved in the international SWAIS 2C drilling project in the western Ross Sea. In addition to scientific participation, it is also a member of the steering group on behalf of Germany and therefore has an influence on the project's key decisions. Around 50 research institutions from the USA, New Zealand, Germany, the UK, Italy, Japan, South Korea, Australia, Spain and the Netherlands are working together on the international project. In addition to the BGR, the Alfred Wegener Institute, the University of Kiel and the Leibniz Institute for Applied Geophysics are also involved in the project from Germany.
The researchers hope that the drilling mission will provide new information on the further development of the West Antarctic Ice Sheet in the face of global warming by obtaining sediment cores. In particular, they want to know whether the Ross Ice Shelf and the West Antarctic Ice Sheet could melt if the Earth's average surface temperature were to be 2 °C above pre-industrial levels. The team hopes that the drilled sediments will provide insights into past periods in which the West Antarctic Ice Sheet was exposed to warmer and more CO2-rich conditions, as predicted for the coming decades and centuries.
In addition, BGR and AWI are pushing ahead with a drilling project on the Ekström Ice Shelf off Dronning Maud Land, East Antarctica, to investigate the disintegration of Gondwana, palaeo-ice streams and past climate changes. The Sub-EIS-Obs project aims to record the volcanic sequences of the so-called Explora Wedge and its overlying sediments as well as the structures beneath the Ekström Ice Shelf. It is assumed that the Explora Wedge is part of the Jurassic Karoo magmatism, which occurred simultaneously in South Africa and East Antarctica as a result of the initial break-up of Gondwana. As preliminary work, a network of reflection seismic profiles has already been established and shallow drilling has been carried out at selected locations. If the resulting findings provide the hoped-for indications of the development from the Gondwana break-up to the change from the greenhouse to the icehouse climate at the Eocene-Oligocene turn, an international drilling campaign will be organised.
Drillings to date
BGR was involved in two international research drilling programmes in the Ross Sea: the Cape Roberts Project and ANDRILL. Both projects served to clarify the tectonic, volcanic and sedimentary development of the Ross Sea and its glacial history.
The Cape Roberts Project (1997-1999) was an international research drilling project that extracted several cores from the sediment fill of the Ross Sea and documented the period from 34 to 17 Ma before present. The aims were to reconstruct climate development from the Cretaceous to the present day, to document the beginning of glaciation, to provide evidence of former warm periods and to examine the links between tectonics and climate, such as the uplift of the Transantarctic Mountains as the condensation core of the glaciation.
The ANDRILL project was developed from the Cape Roberts project. ANDRILL also aimed to reconstruct the tectonic, volcanic, climatic and environmental development of Antarctica from the end of the Cretaceous to the present day. The drill sites drilled between 2006-2008 from the McMurdo Ice Shelf and McMurdo Sound were selected on the basis of the results of extensive preliminary geophysical investigations involving the BGR. With both boreholes, a combined high-resolution sediment core approximately 2400 metres long was obtained for the last 17 Ma to the present day.
Further information on past Sub-EIS-Obs expeditions can be found under the following links:
Sub-EIS-Obs 1
Sub-EIS-Obs 2
Sub-EIS-Obs 3
Literature
Here you will be redirected to the internationale projekt website of SWAIS2C.
Partner
Numerous people from over 50 research institutions worldwide are involved in all international drilling projects. The research organisations and institutions involved come from New Zealand, the United States, Germany, Australia, Italy, Japan, Spain, the Republic of Korea, the Netherlands and the United Kingdom. In addition to the BGR, German participants in the project include the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research (AWI), the Leibniz Institute for Applied Geophysics (LIAG), and the universities of Kiel and Cologne.