The Boomer Sound Source as a Tool for Shallow Water Geophysical Exploration

Abstract

Technical specifications for small seismic sound sources used in seismic profilers may provide details of the pressure signatures as measured on the primary acoustic axis and in the far field but will rarely provide information regarding off-axis emission or of the form of the signatures in the near field. Since shallow water geophysical mapping is now attracting more attention in research establishments and in the commercial sector, off-axis information could become an important issue. The use of a wide angle seismic configuration on a small scale will demand that directional source information be included in data processing activities if the full potential of the data is to be realised. Direct measurement of the full near and far field characteristics of a source are often not practical, however modelling of the acoustic field may offer a tractable alternative and a means of rapidly generating source functions appropriate for advanced data processing. One such modelling approach reviewed here uses a time domain method to synthesise off-axis signatures using a far field, on-axis reference signature.