POSITIONAL ACCURACY


Geographic positions were mostly commonly given in USGS section, township and range or latitude and longitude. When not provided, latitudes and longitudes are those interpolated from the publications that reported the fossil sites. In some cases only a geographic description was given in publications (e.g., the site is located five miles west of Springfield, IL). These descriptions were then transferred to USGS index maps for the 48 states to determine the quadrangle in which the site was located. After determining the quadrangle, the latitude and longitude were taken from the SE corner of the relevant quadrangle and used as the location for the site in the FAUNMAP database. Color coding showing the accuracy of sites is available on the interactive maps.

Accuracy is expressed as:

EXACT if the latitude and longitude were reported.

QUAD PRECISE if the locality description allowed precise placement on a USGS quadrangle map (usually 7.5) or township and range were given.

QUAD APPROX if the description allowed placement on a portion of the map, but was not detailed enough for precise placement.

COUNTY CENTER if the locality information was so lacking that the best resolution was placing it in a certain county.

In general, EXACT and TOWNSHIP imply that the locality is within a 1km radius of the latitude and longitude in the database, QUAD PRECISE within about a 5 km radius, QUAD APPROX within about a 10 km radius, and COUNTY CENTER within a county.

As of 2004 the Landsat images used in the map interface and provided by the JPL WMS service have an offset of 100-200 meters worldwide. JPL was working to fix this but it is unknown when the fix will be completed.

 
Use of this resource in publications should be cited as:
Graham, R.W., and E.L. Lundelius, Jr. 2010. FAUNMAP II: New data for North America with a temporal extension for the Blancan, Irvingtonian and early Rancholabrean. FAUNMAP II Database, version 1.0 this website.