Sediment transport and deposition in the Ingøydjupet trough, SW Barents Sea

• Sediment transport and deposition by ocean currents during the 130 years is studied.
• Strong bottom currents are associated with the Norwegian coastal current.
• This is based on varying SS¯ and decreasing fine sediment supply toward present.
• Stable bottom currents are associated with the North Atlantic current.
• This is based on the stable SS¯ and higher TOC contents.

In this study we have performed a baseline characterisation of sediment properties in four depositional areas of the Ingøydjupet trough in order to investigate the sediment transport and deposition by ocean currents in the SW Barents Sea. Sedimentation rates, by the 210Pb method, were 1.0–2.4 mm/yr and decreasing with distance offshore. Stronger and more variable bottom currents associated with the Norwegian coastal current operate nearshore based on the down-core distribution of sortable silt (SS¯) and sediment fractions (clay and silt). These nearshore stations exhibit a trend of decreasing fine sediment supplies and increasing sand content toward present day. The most stable bottom currents are associated with the farthest offshore station which is under the influence of the North Atlantic Current as indicated by the distribution of (SS¯) and also higher TOC contents (0.6–0.9%) compared to nearshore stations (0.4–0.8%). These baseline findings are of relevance for the petroleum industry in planning environmental assessment and monitoring programs connected to the future expansion of industry activities in this region.