A bathymetric chart of the Gulf of Alaska and approaches covering an area of about 800,000 square nautical miles has been prepared from Coast and Geodetic Survey hydrography, 1925–1957, with a view to defining regional physiographic provinces.
The basic data comprise 90 sounding lines across the gulf, 42,000 miles of graphically recorded profiles obtained during the last 5 years, and detailed surveys of 60 seamounts, seaknolls, and ridges. Tentative names are assigned principal features of the sea floor to facilitate discussion.
The bathymetry and illustrated profiles reveal clearly the form of the Aleutian Trench, two submarine mountains, several seamount chains and groups, a ridge and trough province, a 200-mile trench west of Vancouver Island, a great trough paralleling the West Coast, and an inferred fracture zone extending in several wide echelon bands across the gulf.
The submarine topography is discussed in relation to existing theories of earth science and correlated with features previously mapped on the mainland and in the Central Pacific Ocean.