the Expedition ARKTIS-XIX/4 of the research vessel POLARSTERN ...

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In addition to the deep seismic lines a regional network of multi-channel seismic data
were acquired (Fig. 2-3). Details on the acquisition parameters please see table 2-1.
According to the ice conditions two types of streamers were used. A 3000 m long
cable in the southern part were the ice coverage was less than 30%, and a shorter
600 m long cable in the northern part up to the Greenland Fracture zone with an ice
coverage up to 80%. The lines with the shorter cable terminate more or less at the
shelf break, since the streamer length does not allow an effective removal of the
multiple energy on the shelf. The situation is different with the 3000 m cable. Here,
the lines were extended to the shelf in order to map the deeper structure in the
supposed continent-ocean transition zone. Not very much above the deeper fabric
can be said at the current stage of data processing. North of 75°N the extension of
the Greenland Escarpment was mapped to the junction of the Greenland Fracture
Zone with the shelf. South of 75°N along no seismic line the pronounced basement
high is visible anymore. Here, it might be more in the west buried by thick sediments
or completely vanished.
Fig. 2-3: Location map of the multi-channel seismic lines acquired along the East Greenland margin.
The bold lines were shot with a 600 m cable, the dashed ones with a 3000 m streamer.
To better interpret the seismic structure along the 2D-profiles it was planned to
acquire in parallel to the seismic data acquisition a magnetic grid with a line spacing
of 5 km. A helicopter borne system (Helimag) was used to perform these