The GeoAcoustics GeoSwath Plus sounding system is an interferometric sounding system enabling wide swath areas to be covered in a single pass of the vessel (up to eight times water depth), achieving total isonification of the seabed over large areas. The sounding data captured exceeds the IHO S44 special order survey standard for depth accuracy.
Echo sounders employed include an Odom Echotrac MK1 (200/24khz), an Echotrac Mk2 (200/24khz) and a Bruttour CeeStar (200/30khz) dual frequency echo sounder. All single beam depth data is logged and processed using HydroPro software. Provision has also been made to operate an echo sweep array on both vessels by installing outrigger mounting points and an internal opening between the hulls to attach extra transducers. The outrigger mounting points are also used to suspend the bar check equipment when calibrating the single beam echo sounders.
The velocity of sound in water is measured using Odom’s Digibar and DigibarPro. Changes in salinity and water temperature affect the speed of sound. The sound velocity profiles taken throughout the water column are also used by the GeoSwath system to compensate for ray bending.