Modifying the Seismic Source Array Spectrum to Reduce the Risk of Injury to Marine Mammals

Acoustic injury criteria for marine mammals are well defined. These criteria are applicable to seismic sources. Several studies have suggested that marine seismic sources emit more high-frequency energy than is required for imaging. I show how the extent of the injury zone can be reduced by using a source array with an output spectrum that is partially attenuated at higher frequencies while probably not compromising image quality.