Abstract
The SSN Nautilus obtained the first continuously recorded echo-sounder profile across the center of the Arctic Basin during its 1958 cruise from Point Barrow to the North Pole and then to the Atlantic Ocean. The sounding lines, supplemented by lines from SSN SKATE reveal the following geomorphic features: (1) the Alaskan continental terrace and continental rise; (2) Canada Basin, a flat abyssal plain at the depth of 3850 m; (3) Chukchi Cap, a projection from the Chukchi Shelf with a summit elevation of about 900 m; (4) a continuation of Canada Basin, interrupted by a few sea knolls and having a depth of 3900 m; (5) Central Arctic Rise, a region of smoothly undulatory topography at depths between 2000 and 3700 m, with relief not exceeding 900 m; (6) Central Arctic Basin, an abyssal plain at 3940 m; (7) Lomonosov Ridge, rising abruptly from the basin to a summit at 1290 m: (8) beginning almost at the North Pole, the Eurasia Basin, an abyssal plain sloping south with a depth gradually increasing from 4090 m to 4500 m; (9) a region of rough topography containing numerous sharp peaks and having relief of as much as 1100 m and containing the deepest sounding of the Arctic Basin, 5335 m; (10) Nansen Ridge, a smoothly undulatory ridge rising to 1280 m where crossed.
