Part I. Bathymetric Charts
Published:January 01, 1941
The submarine configuration off the Pacific coast of the United States offers abundant information bearing upon the geologic history of an interesting and complex section of the earth. Until recent years, little if any accurate knowledge of this submerged continental margin was available.
The United States Coast and Geodetic Survey had taken numerous soundings in various areas of immediate importance to navigation during the years since 1850, but these soundings were largely confined to bays, inshore areas, and offshore shoals. In the latter part of the nineteenth century, George Davidson (1887 George Davidson (1897) of the Coast and Geodetic Survey had identified and named a number of the most prominent canyons heading close to the coast.
In 1922, two destroyers of the United States Navy, the Hull and the Corey, ran reconnaissance lines of sonic soundings out from the California coast to 12,000-foot depths at intervals of approximately 10 miles from San Francisco to Point Conception and at intervals of 5 miles from Point Conception to the Mexican border. Largely on the basis of the 5000 soundings made during this survey, a bathymetric map (U. S. Navy, Hydrographic Office Chart 5194) was constructed which gave preliminary knowledge of the many interesting features off the California coast.
This work was purely pioneering in character, and none of the results have been incorporated on the bathymetric charts herewith enclosed.
The United States Coast and Geodetic Survey has, however, recently surveyed the entire area with modern methods and carried these accurate surveys out to 12,000-foot . . .