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How do hydrophone streamers record sound waves during offshore seismic surveys?

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Hydrophone streamers, also known as towed hydrophone arrays, are essential tools used in offshore seismic surveys to detect and record sound waves that have traveled through the water and sub-seafloor strata.1

The process functions as follows:

Sound Generation: A sound source, such as an air gun, generates acoustic waves that propagate into the water and penetrate the subsurface.1
Detection: As these sound waves reflect off interfaces between rock layers with different physical properties, they return to the surface. The hydrophone streamers, which are towed by a survey ship, contain arrays of hydrophones that convert these returning sound waves into electrical signals.21
Recording: The system records both the strength of the returning sound waves and the elapsed travel time. By analyzing these signals, geophysicists can map the structure of the Earth's crust beneath the seafloor.13

These arrays can be configured for two-dimensional (2-D) or three-dimensional (3-D) data collection, with 3-D surveys using multiple parallel streamers to create spatially continuous, high-resolution images of the subsurface.1