In order to determine the mechanisms for rapid ice stream flow, this project will drill several boreholes to the base of Jakobshavns Glacier, Greenland. Borehole measurements of internal deformation, basal water pressure, ice temperature and electrical conductivity at the bed will be combined with short-period measurements of the surface velocity to provide a firm basis for establishing the mechanisms which govern the flow of this fast moving ice stream. Ice core sampling at selected depths within the borehole and sampling of the glacier bed will be undertaken to determine the physical properties and structure of the ice and any existing subglacial material and the role which these properties play in determining the rapid flow of the ice stream. Water transport at the glacier bed will be investigated by following the flow and dispersion of borehole salt injections using electrical conductivity methods. This project is a fully collaborative effort with ETH, Zurich, Switzerland.
