Comparative Numerical Study of VLF Signal Propagation Characteristics for Ocean Bottom and Marine Borehole Arrays
Preliminary results of a numerical investigation of VLF propagation to ocean-bottom and buried sensors are presented. Using an environmental model representing deep ocean basin conditions, both single and multifrequency seismo-acoustic propagation are simulated by means of a new Fast-Field Reflectivity Program. Factors determining correct environmental model selection by using numerical results for sensors (hydrophone and geophone) in vertical and horizontal arrays are discussed. Some implications for VLF propagation of (sub)bottom mode trapping, P to S wave conversion, and multiple reverberations are considered. It is shown that additional studies are required to better identify both signal and noise mechanisms in long-distance VLF propagation.
KeywordsTransmission Loss Synthetic Seismogram Ocean Bottom Seismic Array Ocean Bottom Seismometer
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