Deep-Tow Sonar

Deep-tow sonar is a sonar carried on a towed body flown close to the seabed to image the bottom at high resolution. Towing within tens to a few hundred meters of the floor cuts the slant range, raising resolution and reducing water-column refraction compared with a hull-mounted system, so deep-tow side-scan and sub-bottom profilers resolve features of order centimeters to decimeters at full ocean depth. The vehicle hangs on an armored cable that carries power and telemetry, with depth set by cable scope and ship speed. Deep-tow systems survey hydrothermal vents, wrecks, cables, and manganese-nodule fields.