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Two mooring lines equipped with near-bottom sediment traps were deployed in the axis of the Nazaré submarine canyon at ~1600 and ~3300 m depth respectively. We studied time series of particle flux, composition (biogenic silica, carbonates, organic matter and lithogenic fractions), granulometry, mineralogy and 210 Pb concentration of particulate matter over five sediment trap deployments between October 2002 and December 2004. Current meters equipped with turbidimeters were also deployed at trap depths to monitor the water flow, temperature, salinity and suspended particle concentration. The composition of the collected particles was fairly constant year-round, dominated by the lithogenic fraction and with OC/N ratios in the range 11-30, suggesting an important terrigenous influence inside the canyon. The results show contrasting dynamic environments in the upper (1600 m depth) and middle (3300 m depth) canyon. High current speeds (spring tides up to 80 cm s-1) and high apparent mass fluxes of particulate matter (mean 65 g m-2 d-1 ; maximum 265 g m-2 d-1) are permanent at the shallowest

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