Some principles used in compiling and editing Soviet bathymetric charts are presented. We particularly focus on mapping relief of the ocean floor. We consider various morphologic and morphometric features of the ocean floor and describe how these features are represented on bathymetric maps. Morphologic features are those that are identified from source data but cannot be measured on the original map. Morphometric features are those for which quantitative data (i.e., absolute and relative height, slope gradient, extent) can be derived from source maps. For this analysis, we examine the Western Indian Ocean, and five major ocean-bottom relief features are identified and described for this area: The continental shelf, the continental slope, hollows, local ridges, and midocean ridges. The choice of bathymetric contour interval (h) is the most important factor in accurate editing of ocean floor relief and we describe nine important physical parameters that must be evaluated for identifying proper contour interval. We also describe the methodology for determining optimum mapping scale and the bathymetric scale range. A four-step process for accurate map editing is outlined. This method can be used to edit features of single maps as well as to evaluate the accuracy and visual interpretability between maps.
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