Sub-bottom profiling systems identify and measure various marine sediment layers that exist below the sediment/water interface. A sound source emits an acoustic signal vertically downwards into the water and a receiver monitors the return signal that has been reflected off the seafloor. Other portions of the acoustic signal will penetrate through the seabed and be subsequently reflected as they encounter deeper soil or rock stratums.
Sub-bottom profiling is typically used in mapping sediment stratigraphy, thickness of ash ponds, characterizing benthic habitats, detecting and measuring the thickness of dredged deposits, detecting hard substrate that has been covered by sedimentation, identifying buried objects (such as cables and pipelines), and defining the basement (or bedrock) layer.
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