Backscatter responses and resolution considerations in archaeological side-scan sonar surveys: a control experiment

The backscatter responses of submerged archaeological material remain poorly Understood, To address this, a control experiment was conducted in Belfast Lough during July and August 2001. A selection of material and targets was arranged oil the seabed in varying orientations. in an attempt to replicate the situation found oil a range of archaeological sites where material is exposed on the seafloor. Repeat side-scan sonar surveys of the control array were conducted at variable ranges and fish heights to examine the backscatter responses and resolution of three commercially available side-scan sonar systems, Results indicate that the electro-acoustic specification of the pulse length and the beam angle of the acoustic Sources govern the theoretical resolution of side-scan data. Backscatter data from the control experiment indicate both organic (wood and leather) and inorganic (metals, ceramics, glass and varying aggregate and ballast grades) natural and man-made materials can be imaged using side-scan sonar and a wide variety of archaeological material types and concentrations may be differentiated by their backscatter responses, (c) 2005 Elsevier Ltd. All rights reserved.

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