Bathymetric Maps

geographic charts showing the relief of the seabed by means of isobaths, usually supplemented by notations of the depth. The coloration of the relief of the seabed is given in depth gradations. The bathymetric map is the basic tool for the study of the physical geography and the mapping of bodies of water. Bathymetric maps are used in the exploration for minerals, the fishing industry, and as an important aid to navigation.

The Dutch scientist P. Anselin was the first to use the bathymetric system in the 17th century in charting the depth of the Maas River on a map of Rotterdam (1697).

Until the years 1940–45, bathymetric maps were mainly compiled using linear interpolation of isobaths between soundings and did not show all morphological features of the relief of the seabed. An important step in the development of bathymetry was the compilation (1950) of a 1:2,500,000 scale Hypsometric Map of the USSR; large-scale navigational charts were widely used in compiling the isobaths of this map, and, in addition to depth soundings, the map incorporated the results of geological and geomorphological studies of the seabed and the shores. Since then, formal linear interpolation of isobaths has been supplanted by geomorphological interpretation of measurements, which makes it possible to show the regular typical features of the structure of the underwater relief (World Atlas, 1954; Sea Atlas, vol. 1,1953; Bathymetric Maps of the Atlantic, Indian, and Pacific Oceans, on a scale of 1:10,000,000, published in 1955–56, and other atlases).

The future development of bathymetric cartography depends on the implementation of large-scale echo soundings of the underwater relief and the perfection of the method of geomorphological interpolation. This method gives a scientifically based and geographically reliable picture of the types and forms of the relief of the seabed, based on a model of the profiles, maximum utilization of data on depths, and geological and geophysical data of the seabed. Of special significance among the contemporary bathymetric maps which are being compiled on the basis of new data are the bathymetric maps of the Pacific Ocean on a scale of 1:10,000,000 (1964), bathymetric maps of the Atlantic Ocean on a scale of 1:10,000,000 (1965), and bathymetric maps of the Indian Ocean on a scale of 1:15,000,000 (1963), as well as the Bathymetric Map of the Physical and Geographical Atlas of the World (1964), the Atlas of the Antarctic (1966), and the World Atlas (2nd ed., 1967).

Bathymetric maps are also widely published abroad. The Oceanographic Institute in Monaco publishes and revises from time to time the General Bathymetric Map of the Oceans on a scale of 1:10,000,000. Small-scale bathymetric maps are an integral part of foreign atlases of general geography and topical subject atlases. The new methods of bathymetric cartography—the study of the relief by echo sounding and geological and geophysical interpretation of the underwater relief—are now also used abroad.