PLSS Map

The PLSS is a way of subdividing and describing land in the US. It is used to divide public domain lands (lands owned by the federal gov't). This area encompasses major portions of 30 southern and western states (excluding the original 13 colonies as well as Texas). PLSS maps divide these lands into 6 mile square townships, which are each further divided into 1 mile square sections, which are then divided into quarters, then divided into quarter-quarters and so on. the above map illustrates this concept. Each block within the bold red lines indicates a separate "township" and the smaller sections within each townships are the 1 mile square sections.

The PLSS is a rectangular survey sytem that consists of a series of separate surveys. Most PLSS surveys begin at an initial point, and townships are surveyed north, south, east, and west from that point. The north-south line that runs through the initial point of each township is a true meridian and is called the Principal Meridian. There are 37 Principal Meridians, each is named, and these names are used to distinguish the various surveys. The east-west line that runs through the initial point of the township is called a base line. This line is perpendicular to the Principal Meridian.

Each township is identified with a township(North-South) and range (East-West) designation which indicate the location north south east or west of the Principal Meridian. For example, a township might be identified as Township 7 North, Range 2 West, which would mean that it was in the 7th townships north of a baseline, and 2nd township west of a principal meridian.
Below is a PLSS map illustrating the principle meridians and baselines for the southern states of the PLSS system.

http://www.rootsweb.ancestry.com/~alfrankl/missalalou.jpeg

Cadastral Map

Cadastral maps are maps that show the boundaries and ownership of land parcels. Some show additional information such as survey district names, identifying numbers of parcels, section or lot numbers, etc...

In the US the Cadastral Survey is used by the Bureau of Land Management in maintaining records of all public lands.

The above example of a cadastral map illustrates a small portion of a subdivision (one particular cul-de-sac). In the picture you can see how the land is divided up into individual homeowner's lots. (Clicking on the picture will enlarge it for viewing purposes.)

http://www.aaberginc.com/images/pic/property%20lines.gif

Thematic Map

Thematic Maps are data maps created to portray a specific subject or for a specific purpose. They reflect some particular themes about a geographic area. They portray such aspects of a city, state, region, nation, or continent as social, political, cultural, economic, sociological, agricultural, or any other aspects. In short, thematic maps tell a story about a place.
The above thematic map tells the story (or at least it's end result) of the 2004 Presidential Election of Bush vs. Kerry. It illustrates through color the political orientation of each state at the conclusion of the 2004 election. Using the patriotic colors of red, white and blue for this thematic map are illustrative of its political theme. The colors are also indiciative of each political party's candidate: red for Bush, a republican; and blue for Kerry, a democrat.
http://www.weburbanist.com/wp-content/uploads/2007/06/united-states-political-map.jpg

Topographic Map

Topographic maps use contour lines to portray the differing shapes and elevations of land. They capture the 3-dimensional aspect of the terrain being illustrated on a 2-dimensional surface. (Contour lines are imaginary lines that join points of the same elevation on the land's surface, above or below a reference surface, i.e. sea level.)

The map above is a simple topographic map of the Fuego and Acatenango volcanic complexes in Guatemala. Fuego is one of Guatemala's 4 active volcanoes.
The circular rings (contour lines) illustrate the increasing elevation of each volcanic peak. The largest outer ring indicates the base of the volcano, with each progressive ring illustrating a higher elevation up the mountain, until reaching the volcano's peak (the smallest ring, with highest elevation).
http://www.geo.mtu.edu/volcanoes/fuego/pic/f29.gif

Planimetric Map

Planimetric maps are maps that represent/portray the horizontal positions of features and places using lines and symbols, while vertical information is specifically ignored. They are surface maps with no relief features. An example of a planimetric map would be a street map, or even an organizational flowchart, mapping out the organizational levels of a large company.The above planimetric map gives a detailed layout of a portion of a neighborhood, illustrating the horizontal position of streets, buildings, and even shrubbery. This map use symbols and colors to illustrate features and their shapes, such as the double lines indicating roads, green squiggles which represent trees/bushes, etc... It also portrays underground features, i.e. storage tanks.

http://www.ncdot.org/doh/PRECONSTRUCT/highway/photo/Products/images/Planimetric_map.jpg

Mental Map

Mental maps are described as a person's perception of the world; they are an individual's own internal map of their known world. It represents what the person understands about the locations and characteristics of places at a variety of scales.
This map was drawn by a student in Thailand. It illustrates his own internal perception of the world we live in: where countries are located in relation to one another; the countries that are known to him; his understanding of the relative sizes of countries; etc.
While it may not be precise, this student's mental map illustrates how he perceives the layout of the world, based on his experiences and what he has been taught.
http://go.owu.edu/~jbkrygie/krygier_html/geog_222/geog_222_lo/geog_222_lo13_gr/sketch_proj.jpg