Marine seismic refraction gave access to vertical sections highlighting the geological units defined by the parameter of velocities of compression waves (P wave).
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Seismic refraction (P wave velocities)
The marine surface wave gave for every seismic shot locations one or two vertical profiles of the shear wave velocities of the medium as a function of the depth. Locally inversion of velocities have been identified which is not possible by seismic refraction measurements.
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Marine surface wave – UMASW (shear wave velocities)