On the results of studying ice ridges in the Shokal'skogo Strait, part III: New data

Abstract

The paper presents information on the studies of the first-year ice ridges conducted by the AARI experts in April–May 2018 in the fast ice of the Shokal'skogo Strait (Severnaya Zemlya Archipelago) using hot water drilling with computer recording of the penetration rate. Boreholes were drilled along the cross-section of the ridge crest at 0.25 m intervals mainly. One of the ice ridges had an unusual configuration: the sail crest was on the edge of the perpendicular extended keel crest. Cross-sectional profiles of ice ridges are illustrated. The records of thermodrilling rate revealed the presence of residual ice fragments in the keel of the ice ridges. The sail height varied from 2.9 up to 3.2 m, the keel depth varied from 8.5 up to 9.6 m. The average keel depth to sail height ratio varied from 2.8 to 3.3, and the thickness of the consolidated layer was 2.5–3.5 m. The porosity of the unconsolidated part of the keel was about 23–27%. The distributions of porosity versus depth for all ice ridges are presented and discussed.