Design of a Marine Seismic Reflection Profiling System using Air Guns as a Sound Source

Abstract

Summary It is normally assumed that all the known information about the source wavelet of a seismic trace is contained in the autocorrelation function of the trace. In such a case it is shown that present marine seismic reflection profiling systems must use minimum-delay source wavelets in order to construct Wiener spiking filters from the autocorrelation function. For the source wavelet to be minimum-delay severe constraints must normally be put on the system; in particular, bubble oscillations must always be suppressed in some way, and thus energy is lost. The method proposed here for the design of Wiener spiking filters to aid the deconvolution of seismic traces, formed using air guns as a sound source, demands only that the pressure, volume and depth of each independent air gun and the depth of the streamer be known. This allows all the available energy to be used. The resulting source waveform, as calculated using the theory of Ziolkowski, though not minimum-delay, can be used in the construction of an efficient Wiener spiking filter.