| Abstract: | To specify intelligently a nondynamite source in a marine seismic data-collection system, it is important to use all known parameters of the system—source, receiver, and recording-system characteristics. A technique has been developed to design the far-field pressure pulse of an air-gun array by taking these parameters into account. Important source variables to consider are interaction among guns in the array and the depth of the array. Near-field pressure signatures of individual guns, which are relatively unaffected by boundaries, have been used to‘construct’the far-field pressure pulse of the array by considering these variables. Comparison between constructed pulses and measured far-field pulses shows substantial agreement. Streamer depth and recording-system bandpass should also be considered when designing an air-gun array. Comparison of far-field pressure pulses for several bandpasses clearly shows the importance of considering this variable; e.g., the initial pulse is severely attenuated when a high-cut filter is used. Likewise, an additional filtering effect due to the streamer's proximity to the surface should be taken into account. Design of an air-gun array using the principles just outlined are illustrated by an example. |
