GINS's developped streamer and guns were used. The data were taken at a shot interval of 8 seconds, with analog display at 4 seconds on ship's RAYTHEON line recorder. The seismic source was made up by two guns towed at the port and starboard sides of the stern. Guns' capacity ranged from 0.5 to 1 L each.
A new high resolution gun and a new streamer were developed, built and tested onboard. The used air-guns were built around an original design patented by GIN (V.Efimov). The materials are stainless steel, titanium, poliurethane. The new, high resolution gun was entirely built in titanium.
Two streamers were used. The first, employed an array of 50 ceramic elements (25 mt active) in diesel oil, whilst the second employed an array of 30 ceramic elements (15 m active) in a vacuum poliurethane jacket, contained in a larger poliurethane jacket filled by seawater during deployment. This latter configuration helped to increase substantially the signal/noise ratio. The tow leader consisted of an armoured steel cable, plus a stretch section. Total length to active was aprox. 150 m from stern.
Some lines were run with the two guns synchronized. The air pressure ranged from 70 to 100 Bar, as provided by ship's seismic compressors. The guns were towed at 4-5 m (2-3 m for the high resolution one), whereas the streamer was towed at 11 m.
Figure 21 show an example of the data acquired.
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