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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 whoud 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:
- area,
- boundary (or transition zone),
- at least one factor of homogeneity or sameness, and
- 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.
(
http://geonames.usgs.gov/faqs.html#25)
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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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