Map Terminology

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The science of measuring water depths to determine bottom topography.

A cadastral survey relates to land boundaries and the definition of ownership, limitations of land titles, etc. Derived from “cadastre” meaning a register of land quantities, values, and ownership used levying taxes, the term may properly be applied to surveys of a similar nature outside the public lands, such surveys are more commonly called “land surveys” or “property surveys.”

The science and art of making maps and charts. The term may be taken broadly as comprising all the steps needed to produce a map: planning, aerial photography, field surveys, photogrammetry, editing, color separation, and multicolor printing. Mapmakers, however, tend to limit use of the term to the map-finishing operations, in which the master manuscript is edited and color separation plates are prepared for lithographic printing.
Center fold

Report maps vs Charts:
Special-purpose map designed for navigation or to present specific data or information. The term “chart” is applied chiefly to maps made primarily for nautical and aeronautical navigation, and to maps of the heavens, although the term is sometimes used to describe other special-purpose maps.

Chart, nautical:
Representation of a portion of the navigable waters of the Earth and adjacent coastal areas on a specified map projection and designed specifically to meet requirements for marine navigation. Included on most nautical charts are depths of water, characteristics of the bottom, elevations of selected topographic features, general configurations and characteristics of the coast, the shoreline (usually the mean high water line), dangers, obstructions and aids to navigation limited tidal data, and information about magnetic variation in the charted area.

Inset Map:
A smaller map or chart inset within a larger map or chart that shows greater detail of an area on the chart.

Recognition Profile:
A view of an area as it would be seen from the water, and including any noticeable landmarks, like churches, lighthouses, rivers, and more. These are often included on nautical charts in order to help sailors recognize what part of the land they are looking at.

A technique for establishing the distance between any two points, or the relative position of two or more points, by using such points as vertices of a triangle or series of triangles, such that each triangle has a side of known or measurable length (base or base line) that permits the size of the angles of the triangle and the length of its other two sides to be established by observations taken either upon or from the two ends of the base line. (from
This technique can be seen in many survey and report charts. Note the many straight lines used for triangulation in harbor areas.