Low Frequency Sub-Basalt Imaging

A-05 LOW FREQUENCY SUB-BASALT IMAGING Summary 1 Ocean margin basalts are extremely heterogeneous and scatter the seismic energy of the conventional seismic reflection system. To observe sub-basalt reflections the system should be modified to emphasize the low frequencies using much larger air guns and towing the source and receivers at about 20 m depth. The rationale for this approach is supported by synthetic seismograms over a realistic 1-D earth model. In the summer of 2001 we obtained data over basalt in the North-East Atlantic using a system modified to incorporate these ideas. Introduction ANTON ZIOLKOWSKI 1 PETER HANSSEN 2 ROBERT