Services

Side Scan Sonar Surveys

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We use an Edgetech 4125 high frequency side scan sonar system with a dual frequency tow-fish.

The system consists of a towed underwater fish which sends out short high frequency, high intensity sound bursts which are beamed from either side of the fish in a direction perpendicular to the direction of travel.

The acoustic beam is narrow in the horizontal plane yet sufficiently broad in the vertical plane to produce echoes from the seabed to points 150 metres or more abeam of the transducer.

These echoes, once detected by the transducers, are sent via the tow cable to the recorder which electronically processes the signals and prints them, line by line, to produce the sonar image on an Ultra 200 series recorder.

For operations in confined spaces such as in shallow water or close to known obstructions we use an Odom sonar. This allows us to work up very close to quay walls and other vessels without the snagging problems associated with towing a fish astern of the survey vessel.