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USGS 1:6000 (Quarter-Quarter 7 1/2 Minute) Quadrangle Index
This is a mathematically generated grid in which each polygon represents one quarter of the already quartered 225 second (or 3 3/4 minute) data resource, or a quarter-quarter of... -
USGS 1:24000 (7 1/2 Minute) Quadrangle Index
Mathematically generated grid representing USGS 7 1/2 Minute Quadrangle Map outlines. Quadrangle names and standard identifiers are included with the data set. -
USGS 1:12000 (Quarter 7 1/2 Minute) Quadrangle Index
This is a mathematically generated grid in which each polygon represents one quarter of a standard USGS 7 1/2 minute quadrangle. The result is a 3 3/4 minute quadrangle layer... -
USGS 1:100000 (1 by 1/2 Degree) Quadrangle Index
USGS 1:100,000 scale Quadrangle Map Index derived from the larger scale double precision 7 1/2 Minute Quadrangle Index. -
USGS 1:250000 (2 by 1 Degree) Quadrangle Index
USGS 1:250,000 scale Quadrangle Map Index with quadrangle name and standard identifiers.
