As part of RV Polarstern cruise PS74, three seismic refraction profiles were collected across the East-Greenland shelf and margin to gather new information on the tectonic and glacial history of East Greenland and its ice shield. The acquired data set covers data from a total of 51 stations, including 4 on land stations. The seismic refraction line AWI-20090100 was in the prolongation of the Kong Oscar Fjord across the Kolbeinsey Ridge. It supplements profiles gathered more in the north in 2003. The second set of profiles (AWI-20090200 and AWI-20090250) was located in the Boreas Basin and terminated at the mid-ocean Knipovich Ridge. Here, in addition, a seismological detection array was deployed for 10 days recording the seismicity of the ultra-slow ridge between two magmatic segments. The seismic energy was generated by an array of 8x8.3 L G-guns, fired every 60 s at 200 bar. The refracted signals were collected by DEPAS LOBSTER (Longterm Ocean Bottom Seismometer for Tsunami and Earthquake Research) instruments equipped with three-components ocean bottom seismometers (OBS) and a hydrophone. The onshore stations comprised by 3 x 3 4.5 Hz-geophone chains (REFTEK). Except one OBS station, all instruments were successfully recovered after finishing the experiment. Survey information and detailed data acquisition parameters for the profiles are documented in the expedition report (Jokat, 2010) and in a metadata-file listed below.The present data set provides primary data concerning the refraction seismic profile AWI-20090250. 6 OBS stations were deployed along a ~130 km long line. The data set comprises (a) a table with compiled metadata and information on all stations, (b) an overall ReadMe-file with information on the whole seismic refraction experiment, and (c) seismic refraction data in segy-format stored as big-endian (_be.sgy) and little-endian (_le.sgy) for each channel. The EBCDIC-Headers enclosed in the seg-y files document metadata, recording parameters, and the seismic data processing sequence. Navigation information is included in the seg-y headers.
