Geoacoustic inversion from towed array data at the New England Mud Patch

Geoacoustic structure and properties are estimated for muddy and sandy sediment layers along a 25-km seabed transect on the New England Mud Patch south of Cape Cod. Acoustic reflection data were acquired with the Three Octave Research Array (THORA) of the Office of Naval Research (ONR), which is a towed hydrophone array, and a towed source emitting linear frequency modulated sweeps. The data have been processed to obtain reflection coefficients as a function of angle and frequency, which were inverted to estimate geoacoustic seabed sediment properties. The transect is divided into lateral segments, and the seabed is parameterized by two-dimensional models of homogeneous layers of variable thickness. Meter-scalelateral variability in the mud–sand horizon is observed and comparisons to results of previous studies are made. Work funded by ONR Ocean Acoustics Program.