Seismic investigations of the Greenland ice sheet at EGIG points

The compressional and the shear wave velocities in the Greenland ice sheet are derived from seismic records of the EGIG 1959. Further the variation of velocities in the firn and the dependance of Poisson's ratio from depth are determined. At Station Centrale, two P-waves are recorded from underground layers. Their velocities show that the ice basement consists of crystalline rocks. The P-wave velocities derived from reflections agree well with those obtained by refraction shooting. From this agreement results that the ice is ± homogenous and ± isotropic for Pwaves. The elastic constants for isotropic ice are calculated. Finally the temperature dependence of the velocities is discussed.

Thermal conductivity and heat flow measurements from cruise Planet69, 4-21 August 1969, Norwegian Sea

This is a report about a joint scientific venture of German and Norwegian Institutes in an area between Latitude = 66°45' N and 68°30' N and Longitude 1.0° E to 7°30' W. The chief scientist's report gives an outline of the cruise. The preliminary contributions by the scientists deal with results of gravity at sea, magnetic and geothermic measurements, the seismic shooting, results of continuous seismic reflection work, some refraction seismic results and with the observations of the ship's weather station.