USGS Open-File Report 2010-1095

A Review of Aeromagnetic Anomalies in the Sawatch Range, 
Central Colorado 

COLOR SHADED-RELIEF IMAGES

Color shaded-relief images of the magnetic, gravity, and terrain data 
are available as two 'tif' images, which are georegistered and show 
latitude/longitude tick marks.  One of the images has no extra annotation 
so that it can be co-registered with other overlays; a second image (with 
the phrase 'annot' in the file name) has a scale bar and other text for 
map plot purposes.

Each image is made up of two separate data files:  a 'tif' file and 
a 'tfw' file, which contains projection information for georegistration.


IMAGE FILES                DESCRIPTION
-------------     -------------------------------------------------------
cc_mag_rtp           Residual magnetic map, reduced to the pole (RTP).
                     Declination and inclination of the Earth's field 
                     were assumed to be 10.5o and 66o respectively.

cc_mag_med           Bandpass-filtered RTP magnetic map.
                     This filter was designed using matched filtering 
                     (Phillips, 2001), which resulted in cutoff values of 
                     0.44 km for the high-pass wavelengths, 1.47 km for 
                     the "medium" wavelengths, and 11.3 km for the low-pass 
                     wavelengths.

cc_mag_low           Low-pass filtered RTP magnetic map.  Filtered as above.

sawatch              A subset of the 'cc_mag_med' grid, showing the 
                     color-shaded relief of the medium-filtered
                     magnetic data.  Numbered polygons are also shown.

cc_isograv           Isostatic gravity map, subset from the state gravity
                     map of Colorado (Oshetski and Kucks, 2000). 

cc_topo              Topographic map.