f New perspectives for multisource vibroseis technique for 3D land acquisition

Looking at the literature simultaneous recordmg with two vibrators groups has been undergoing refinements for approximately fifteenth years starting from the Combisweep technique (Werner and Krey, 1977) and Encoded sweep (Bernhardt and Peacock, 1978; Edelmann et al. 1978). Silverman (1977) and Anstey (1979) requested patents in the U.S.A. Garotta (1983 and 1985) stated the basis for the efficient both signal and polarity combination encoding for simultaneous multi source recording. The reason for this high interest on the topic are mainly economical. As a general rule, simultaneous data recording improves field efficiency allowing a reduction of the survey duration and a correspondent colt reduction. With the actual oil price any kind of money saving also in exploration geophysics have to be carefully considered by any Company Management.