Locational and Coordinate Systems - A Primer of GIS: Fundamental Geographic and Cartographic Concepts - page 110

TABLE 5.1. The Parameters for the Three SPCS Zones
in Minnesota Using the 1927 North American Datum*

Southern
Standard
Parallel

Northern
Standard
Parallel

Semimajor
Axis (m)

Semiminor
Axis (m)

Longitude
of Origin

Latitude of
Grid Origin SPCS Zone

North 6378206.4 6356583.8 47 02 00 48 38 00 -93 06 00 46 30 00

Central 6378206.4 6356583.8 45 37 00 47 03 00 -94 15 00 45 00 00

South 6378206.4 6356583.8 43 47 00 45 13 00 -94 00 00 43 00 00

*See http://rocky.dot.state.mn.us/geod/projections.htm#27MSP for further information.

United States. Geographic information collected with the later NADCON or
HARN improvements will differ from NAD 1983 data.

The U.S. National Grid
The U.S. National Grid (USNG) was standardized in 2001 in response to
needs for a single coordinate system for the entire United States, especially
for location-based services for mobile phones, GPS, and other navigation
devices. The USNG can be extended to include coordinates for locations
anywhere in the world. It is not intended to replace the SPCS, nor other
coordinate systems, but it provides a coordinate system with national scope.
It is a hierarchical system, using the grid system specified in the Military
Grid Reference System (MGRS). The coordinates are also identical with
UTM coordinates in areas of the United States. Coordinates can be specified
in two precisions. For example, the location of the Washington Monument
in Washington, DC, is:

State-Plane Coordinate System (SPCS) zones using the North American Datum
1927 (NAD 1927).