LARGE-SCALE SEDIMENTATION ON THE GLACIER-INFLUENCED POLAR NORTH-ATLANTIC MARGINS - LONG-RANGE SIDE-SCAN SONAR EVIDENCE

Long-range side-scan sonar (GLORIA) imagery of over 600,000 km(2) of t he Polar North Atlantic provides a large-scale view of sedimentation p atterns on this glacier-influenced continental margin. High-latitude m argins are influenced strongly by glacial history and ice dynamics and , linked to this, the rate of sediment supply. Extensive glacial fans (up to 350,000 km(3)) were built up from stacked series of large debri s flows transferring sediment down the continental slope. The fans wer e linked with high debris inputs from Quaternary glaciers at the mouth s of cross-shelf troughs and deep fjords. Where ice was slower-moving, but still extended to the shelf break, large-scale slide deposits are observed. Where ice failed to cross the continental shelf during full glacials, the continental slope was sediment starved and submarine ch annels and smaller slides developed. A simple model for large-scale se dimentation on the glaciated continental margins of the Polar North At lantic is presented.