The bi-azimuthal scattering distribution of an abyssal hill

摘要: High-resolution bistatic images of a typical abyssal hill on the western flank Mid-Atlantic Ridge are made with low-frequency towed-array system operating remotely at 1/2 convergence zone (∼33.3 km) stand-off. Comparison modeled images, generated from high-resolution supporting bathymetry sampled 5-m intervals, roughly wavelength scale, reveals that steep scarps return strongest echoes because they project largest area along acoustic path source to receiver. Prominent returns deterministically image scarp morphology when cross-range axis system’s resolution footprint runs axis. Statistical fluctuations inherent in scattered field prevent distinguishing smaller-scale anomalies scarps, such as canyons and gullies (∼100–200 m scale), would otherwise be resolvable range, certain geometries. The mean bi-azimuthal scattering distributions two major identical a...