RIDGES IN THE BARENTS SEA

摘要

Three ridges have been examined with respect to geometry, morphology and physico-mechanical properties in the Barents Sea close to the island Hopen in May 2002, 2003 and 2004. The keel depth varied from 5.7 to 15 m, the average keel depth to sail height ratio varied from 2.9 to 4.8, and the thickness of the consolidated layer was 1.4-1.5 m estimated from temperatures and 1.7-1.9 m from mechanical drilling. The porosity of the unconsolidated part of the keel was about 30 % in two ridges and about 10 % in the third. The latter is probably due to measurement difficulties and not the real porosity. Altogether 220 block were examined and the average block thickness was 0.48 m, the average length/thickness, the width/thickness and the length/width ratios were: 3.9, 2.6 and 1.6 respectively. There was considerably less spread in the length/width distribution than in the other ratios. The salinity of the level ice and the consolidated layer was about 4 to 5 ppt and no systematic difference was found. The rubble had partly higher salinity (6.8 ppt in 2003) and partly lower (2-4 ppt, 2002 and 2004), and I believe this is a results of different stages in the deterioration of the rubble in the different years. This is also reflected in the porosity measurements.