Geomorphological Maps

maps that characterize the relief of the earth’s surface according to its physiognomic features (its morphography and morphometry) and according to its origin and age.

In representing the origin of relief the various endogenous and exogenous factors that caused it are also shown. General, broad-content (comprehensive), geomorphological maps may be distinguished from particular maps, which depict separate (particular) topographical features—morphometric, structural-geomorphological, and others. General geomorphological maps, designed to meet the needs of the broadest range of users, are being compiled systematically in the course of the comprehensive geological surveying of the entire territory of the USSR. In addition, special-purpose geomorphological maps are compiled to help solve particular scientific or national economic problems. They are used, for example, in prospecting for some types of mineral deposits and in road or hydraulic construction. Geomorphological maps of underwater topography are compiled for characterizing the topographical features of ocean and sea bottoms; these maps are also classified as general, particular, and special-purpose. These maps generally have a small scale and less detail owing to the fact that little is known of underwater topography and of the processes shaping it. The morphology, dynamics, and origin of littoral zone topography are represented on coastal geomorphological maps. On geomorphological maps relief data are represented by a system of superimposed designations such as color backgrounds, hachures, symbols, isolines, and indexes.

Geomorphological maps may be synthetic or analytic, depending on the degree of generalization and on the method of representing geomorphological indicators. On synthetic maps natural morphological complexes or morphogenetic types of relief may be distinguished, depicted by means of color backgrounds and characterized by synthetic geomorphological backgrounds. Analytical maps depict relief elements or elementary surfaces having the same origin and age. On these maps morphographic and morphometric relief features are represented by isohypses, point and line symbols, and height marks, genesis is indicated by a color background, and age is shown by the intensity of the color background. Each genetic relief element category is represented by its own particular color. Relief elements and forms not expressed on the map’s scale, as well as relief elements and forms of structural-denudational and tectonic origin, are represented by color point and line symbols and by different hachuring patterns. An analytic map is appended as an illustration; the principal morphographic and morphometric relief features are included in the map’s legend. Geomorphological maps serve as the basis for the compilation of maps dividing territories into morphological subdivisions such as geomorphological regions, provinces, areas, and districts. Examples of survey geomorphological maps are the 1:4,000,000 Geomorphological Map of the USSR (1960), the 1:5,000,000 Geomorphological Map of the USSR (1961), and the 1:2,500,000 Geomorphological Map of European Russia and the Caucasus (1970).