The preceding results of the Deep Sea Drilling Project/International Program of Ocean Drilling (DSDP/IPOD) have shown that inspection of borehole cores in the Southern Ocean and around Antarctica are necessary for reconstruction of the development of the Atlantic Ocean and for the understanding of the sedimentary deposition which is strongly affected by the palaeo-oceanographic processes. As the geological development of the Weddell Sea plays a key role for the reconstruction of the south-american and african part of the former supercontinent Gondwana, the Federal Institute for Geosciences and Natural Resources (BGR) has decided to conduct a synoptic geophysical survey in the eastern Weddell Sea and in front of the eastern Antarctic continental margin. This survey has been designed as a prearrangement for a larger "presite" program for preparation of future DSDP/IPOD sites. The main focus of the geophysical survey during the first leg of cruise BGR78 from 5th of January to 13th of February 1978 with M.S. EXPLORA has been put on the continental margin of the south-eastern Weddell Sea and eastern Antarctica between 20°E and 30°W and south of 67°S. Especially the lines BGR78-03 to BGR78-23 of seismic reflection measurements have been carried out in this region which were affected by heavy ice conditions at this time. Additionally, on 43 stations sonobuoy refraction measurements have been conducted.