Measurements of near-bottom Turbidity and Currents at Svale, Block No. 6608/10, June-August 2003

Abstract

Statoil ASA is conducting design studies for the Svale oil field which is located on the shelf at 66oN, 8oE. In connection with this, measurements of water current and turbidity near bottom were performed during the period 15 June-4 August, 2003. In addition, grab samples of sediments were collected for further analysis. Currents at 2 m above the bottom ranged between close to zero and up to 12 cm/s, with average speed of 4 cm/s. Currents at 7.5 m above the bottom showed a highest measured value of 17 cm/s. The direction of the dominating water transport (volume flux) was towards the NW. The most dominant particle size of grains were around 4 µm (32%). 61.6% were classified as silt and 36.2 % as clay. Turbidity values at 2 m above the bottom were mostly in the range 0.1 - 0.5 FTU and at 6.5 m above the bottom the values were around 0.4-0.5 FTU, with a slightly increasing trend with time. The minimum required steady current for remobilization of the bulk of the sediments is probably around 80 cm/s. It was concluded that no episodes of suspended sediments were recorded at Svale.