Geology & Geophysics
An understanding of the stability or otherwise of the floating ice shelves surrounding the Weddell Sea over the last few thousand years is needed to place recently observed changes within a long-term context. This Expedition will use geological and geophysical methods to investigate the former position of the grounding line, which is the point at which the ice sheet ceases to be in contact with the underlying seafloor.
Sediment cores collected from close to the ice front can show how the grounding line position has changed over time; for example, coarse grain sizes are more likely to be produced when the grounding line was close to the core site. In addition, the use of downwards-looking sonar on Autonomous Underwater Vehicles (AUVs) can enable the identification of glacial landforms that were produced during former periods of relative stability in the grounding-line position.