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"The man who makes no mistakes does not usually make anything". disclaimer

  • The maps used to illustrate an atlas area and research activities occurring within the area are provided for illustrative purposes only and are not to be used for navigation, considered precise, or used in any way which would endanger lives or property.

  • Boundaries, borders, areas, etc. as used within InfoBank are illustrative, not official. The areas used within InfoBank are based on a combination of political, physiographic, project, and usability considerations.

There are no official designations for regions at any level of government. The U.S. Board of Geographic Names, which is responsible by law for standardizing geographic name usage throughout the Federal government, is often asked for official names and boundaries of regions. However, there are none officially. Regions are application driven and highly susceptible to perception. Sometimes, people might agree on the core of a region, but agreement deteriorates rapidly outward from that core. The criteria or application would have to be defined, such as:
  • "physiographic" (this would include parts of States, but there is more than one system);
  • "political" (definite disagreement based upon perception);
  • "cultural" (unlimited variables); and
  • other applications.
Generally, geographers use four (4) generic requirements for a region to be formed:
  1. area,
  2. boundary (or transition zone),
  3. at least one factor of homogeneity or sameness, and
  4. a process to drive the region or to keep it functioning as a region.
The American Standards Institute (ANSI) has taken the same approach. One can be sure that is anyone or any organizations announces standards for regions, it is only their own based upon their own needs or application. For more information contact the GNIS Manager.   (

Issues: Offshore boundary lines are measured along an arc over the earth's ellipsoidal surface (chord length); therefore, arc distance varies with latitude and azimuth corresponding to variations in the radius of the earth's surface. As a result, the arc length must be computed (in three-dimensional space) separately for each stretch of coastline, even though the projection distance remains unchanged (Ball 1997). Many boundaries have been created using a buffer function in a geographic information system. This process does not take into account chord length or distortion due to projection and often may result in an inaccurate representation of the "envelope of arcs." Accordingly, the GIS boundary data may not accurately reflect the official or actual boundary. ( FGDC Marine Boundary Working Group)
Some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented without the approval of the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the responsibility of the user.

"The man who makes no mistakes does not usually make anything" -- Edward J. Phelps

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