Seismic surveys use extremely loud sources of sound to penetrate the sediments and rocks under the sea to determine their structure, and to better understand the geology of a region.

In the marine geoscience context, such surveys usually tow an array behind a ship consisting of a "boomer" or "pinger" which produces loud bangs underwater, usually by the sudden release of high pressure air, and behind that, an array of hydrophones (underwater microphones) which can then pick up the echoes from the sediments and rock strata below. This information is then used to create maps of the structure of the sediments and rock strata, using signal processing techniques and special software to interpret the echoes into a model of the subsurface geology.

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