U.S. Geological Survey Open-File Report 2009-1156

High-resolution aeromagnetic survey to image shallow faults,
Poncha Springs and vicinity, Chaffee County, Colorado

Georegistered digital files included with this report are vector files 
representing the interpreted faults.  The files are in shapefile format,
a set of files with names that have the same prefix and suffixes of .prj,
.shp, .shx, and .dbf.  Visit the ESRI Web site (http://www.esri.com)
for more information.  Two sets of files are available:  (1) faults 
interpreted with high confidence (prefix of psmagflts and psmagfltsNAD27)
and (2) faults interpreted with less confidence (prefix of psmagflts_proposed
and psmagflts_proposedNAD27).  Projections are Universal Transverse Mercatur
Projection, zone 13, with distances in meters.  Files with “NAD27” in the 
prefix are projected using the North American Datum of 1927; the others are 
projected using the North American Datum of 1983.