A lack of correlation between air gun signal pressure waveforms and fish hearing damage

Abstract

Offshore marine petroleum seismic surveys involve the repetitive use of intense, short bursts of low-frequency noise, the reflections of which are used to image subsea geology. The seismic signal is produced by a spatial array of sources, usually air guns that violently release high-pressure compressed air into the water column. Although the signal produced by a single air gun is largely omnidirectional at low frequencies (typically, most energy over 10–150 Hz), the signal received by a spatial array of individual air guns is highly directional and dependent on the array configuration and receiver orientation.