Ground Penetrating Radar

For mapping glacier flow structures and the glacier-bedrock interface a 'GSSI SIR 10 A and GSSI SIR 20A were used with a maximum time window of 10,000 ns. A 35MHz antennae-pair (Radarteam AB-SE-40), a 200MHz antennae-pair, and a single 500MHz antenna are pulled by a Nansen Sledge, which carries the control units, generator, and solar panels. A Trimble 5700 differential, kinematic GPS, provides absolute positioning of the GPR data and allows survey of the glacier surface topography. GPR and GPS measurements are taken in kinematic mode, every 5-15 seconds ≈ 10-30m.

Fig. 12: Photo showing Nansen sledge carrying GPR and crevasse rescue equipment (from Watson, 2007)