Seabottom roughness study using a hydrosweep–multibeam system

Seabottom profiling using a multibeam echosounder is a well-known method to acquire a high-resolution and high-density data set for bathymetric mapping of survey area. The use of multibeam echosounder backscatter signals for bottom roughness characterization is a modern technique. Here, the model results of seabottom backscatter data using a hydrosweep-multibeam system, from some of the geologically well-known areas of Southern Oceans, are presented. Using the capabilities of multibeam systems, angular backscatter strengths are determined employing various corrections. Different bottom backscattering modeling techniques like the composite roughness [Jackson et al., J. Acoust. Soc. Am. 79, 1410–1422 (1986)] and two-layer Helmholtz–Kirchhoff model [Talukdar et al., J. Acoust. Soc. Am. 97, 1545–1558 (1995)] for estimation of bottom roughness is applied. Various seabottom parameters like root-mean-square (rms) relief height, correlation lengths, attenuation coefficients, and layer thickness using the two-layer Helmholtz–Kirchhoff model are calculated. The interface roughness parameters, i.e., slope and intercept values, and volume roughness parameters are computed using the composite roughness theory for the same geological areas.