f G.I. Gun sea trials

The search continues for the ideal marine seismic source. Each of the currently available sources has its good and bad points. Air guns suffer from long-period bubble oscillation, and so have to be used in large arrays. Water guns have good short signatures, but these are non minimum phase. A 'bubble-free' airgun would be a very attractive source, and the G.I Gun is an attempt to attain this (Pascouet 1989). This paper presents results from trials of the G.I. gun, and a comparison between G.I. guns and water guns.