Tuesday, November 27, 2012

Planimetric Map



A planimetric map is a surface map with no relief features. It shows only the horizontal position of features, without regards to elevation. This map of downtown Chicago is considered a planimetric map because it shows the roads of the city in relation to one another. It is not possible to distinguish the elevation of the area from this map. 

Topographic Map


Topographic maps are considered to be a large-scale maps showing relief. These types of map use contour lines to portray the shape and elevation of land. They also capture 3-dimensional aspect of terrain on two-dimensional surface. Contours are imaginary lines that join points of equal elevation on the surface of the land above or below a reference surface as mean sea level. This particular map can be considered a topographic map because it shows the different elevations with shaded relief. Due to this maps large scale and quantitative representation of relief is it able to qualify as a topographic map. 


Mental Map


A mental map is a map in an individual’s mind, which reflects the knowledge and prejudices of that individual. Such a map reflects the individual's perceptions of, and preferences for, different places and is the result of the way in which an individual acquires, classifies, stores, retrieves, and decodes information about locations. Mental maps may also include images of locations, thus, different locations may be ranked in order of attractiveness. This map is an example of a mental map because is captures the person’s point of view, it obviously is not geographically accurate but is shows how this particular individual perceives their surroundings. 


Thematic Maps



A thematic map shows information on a topic superimposed over a base map. These types of maps or charts are designed to show a particular theme connected with a specific geographic area. They can portray physical, social, political, cultural, economic, sociological, agricultural, or any other aspect of a city, state, region, nation, or continent. The map displayed above is considered a thematic map because it shows the estimated median household income (the theme/topic) of the United States. The different variations of the median household incomes are shown using different shades of red. 

Cadastral Maps


A cadastral map is a legal map for recording ownership of property. The map describes boundaries and ownership. Cadastral mapping is done from hard copies of the administrative maps, which specifies the details of each plot, roads, railway lines, water bodies, vegetation, etc. Cadastral mapping leads to effective management of public land records. This map is an example of a cadastral map because it shows the precise locations, and dimensions of individual parcels of land. It also shows all the land parcels in relation to one another and to the adjoining roads. 


PLSS Maps


PLSS stands for Public Land Survey System. This surveying method was used historically over the largest fraction of the United States to survey and spatially identify land parcels before designation of eventual ownership, particularly for rural, wild or undeveloped land. This map shows the extent of the system in the United States. This area encompasses major portions of 30 southern and western states. The PLSS is also many times referred to as a rectangular survey system.