Influence of array configuration on the application of the image source method for the characterization of volume heterogeneities in the seafloor layers

Abstract

In the context of seafloor characterization, the image source method can be used as a technique to characterize the sediment sound-speed profile with low computational cost. This technique is based on the analysis of the seafloor reflected acoustic waves as a collection of image sources whose positions are linked with thickness and sound speed of each sediment layer. When dealing with real data, the calculated sound-speed profiles are subject to important fluctuations that are partially due to the differences between a true seafloor and the assumption of fluid layering with smooth interfaces. For a better understanding of the fluctuations, an algorithm based on the image source method is used to remove layer reflections from the recorded signals. From these filtered signals, performing imaging of the sediment volume fluctuations can provide information on the seafloor heterogeneities, such as structures buried in the seabed. This work evaluates the effectiveness of the filtering algorithm for different array configuration.