A non-destructive non-contact method of the sea-bottom structure investigation

The paper describes a nondestructive noncontact method for investigating the sea-bottom structure using hydroacoustic and laser radiation. A practical implementation of this method is also presented. The research complex incorporates a state-of-the-art low-frequency hydroacoustic radiating system and a system of coastal laser strainmeters arranged in the specially selected sea waters and coastal grounds. The hydroacoustic radiators are used to generate a seismic signal. Seismic superficial waves are recorded by the coastal laser strainmeters. Optical parts of the strainmeters are constructed as the unequal-path Michelson interferometer where the frequency-stable helium-neon lasers serve as emission sources. A preliminary model of the sea-bottom testing ground has been developed by application of geologic-geophysical procedures. The model-based analysis of the timing data of the recorded seismic waves was carried out. The prospectivity of the used method was proved.