Ocean-bottom reflectivity (a point of view)
The analysis procedures for extracting bottom loss values from pulsed acoustic signals that have interacted with the ocean bottom do not inherently consider sub-bottom refraction and reflection of sound, which are important effects at low frequencies (i.e.; < 500 Hz). Sound returning from the sub-bottom can constructively interact with sound reflected from the water-sediment interface, yielding negative bottom loss results. To support this premise a Fast Field Program (FFP) time domain model simulation of a bottom loss measurement was performed in which the lateral wave was the only additional arrival interacting with the bottom reflected wave arrival. The simulation demonstrates a plausible cause for anomalous bottom loss results and suggests that propagation models must accommodate the environmental description of both the water column and ocean bottom.
SourceIn: Ocean Acoustic Modelling (SACLANTCEN Conference Proceedings CP-17), Part 4, 1975, pp. 14-1 - 14-13.
Santaniello, S. R.;
DiNapoli, Frederick R.
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