Abstract:

Ocean acoustic interferometry refers to an approach whereby signals recorded from a line of sources are used to infer the Greens function between two receivers. An approximation of the time domain Greens function is obtained by summing, over all source positions
stacking, the cross-correlations between the receivers. Within this paper a stationary phase argument is used to describe the relationship between the stacked cross-correlations from a line of vertical sources, located in the same vertical plane as two receivers, and the Greens function between the receivers. Theory and simulations demonstrate the approach and are in agreement with those of a modal based approach presented by others. Results indicate that the stacked cross-correlations can be directly related to the shaded Greens function, so long as the modal continuum of any sediment layers is negligible.