USGS Quadrangles (7½ Minute Topographic Maps) include the
map image, and borders (map collars) that surround each map image.
Maps that have their
collars clipped are called 'seamless' maps. Maps that include the original borders are
called 'collared' maps.
The black line that
separates the map image and the map collar information is called the 'neat line'.
Many digital mapping solutions offer products with 'seamless maps'. At first glance
these products may appear to be more convenient than maps with collars (or borders), but
they do have very serious shortcomings.
The supplementary information included in the collars is as important
as the the map image. If you plan to use seamless digital topographic maps
for filing real estate, mining, mineral or petroleum claims and reports,
make certain that a seamless map is acceptable. Many filings require
standard quadrangles. In addition, many seamless maps are considered 'new
works' and copyrighted, they are not suitable for distribution or
professional use.
All iGage Mapping Corporation products include the map collars. All Topo Maps
1:24,000 scale and 1:63,360 (Alaskan) quadrangles can be converted on demand to seamless
map stock using the included BigTopo [ see BigTopo
Tour ] tool, but the collars are by default available and
shown in the viewer.
