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Throughout the world, active and passive continental margins are cut by marine canyons that form highly dynamic and complex seafloor structures. Sediment transport and landslides are the dominant processes shaping canyon topography. Break-offs at the head and flanks of a canyon often continue upslope, leading to retrograde terrace formation. As canyons often form close to inhabited areas, mass movements in canyons pose a potential threat to settlements and underwater structures. Despite studies of canyons on active and passive continental margins, few direct comparisons have been made using field data. This project aims to compare canyon systems on an active and a passive continental margin (Palliser and Pegasus canyons) off New Zealand. A frequency-size relationship of landslides in canyons will be established, taking into account systematic differences between active and passive margins. The factors that determine the size and location of a landslide will also be determined. The study of topographic amplification effects of canyons on earthquake waves will be included. The integrated analysis of the data should lead to an improved assessment of the hazards and risks of landslides in canyons on active and passive continental margins.