Figure 9. Upward-looking sonar record showing the draft of the bottom of the sea ice cover obtained by a Soviet submarine in the vicinity of Lat. 78° and Long. 75° north of the Island Vize while on transit on a trip to the North Pole, October 1983. The notations on the chart state that 10 mm = 1 minute = 330 m. The vertical scale (between the horizontal lines) is 1 m.