U. S. Geological Survey Open-File Report 02-205
Sweeney, Grauch, and Phillips
Merged digital aeromagnetic data for the Middle Rio Grande and southern Espanola
basins, New Mexico

DESCRIPTION OF IMAGE FILES 

Color shaded-relief images of the final total-field and reduced-to-pole
magnetic data are available in a variety of formats. TIF images show latitude/
longitude tick marks only; they have no extra annotation so that they
can be used with other overlays.  PDF images have scales and text for map plot
purposes.  All the formats were derived originally from color shaded-relief 
displays created by OASIS/montaj(TM)*, using a sun azimuth of 90 degrees (east).
Color scales are the same for each image, which are displayed on the PDF images.  
The image files are described briefly below.

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GEOGRAPHICALLY REGISTERED TIF FILES
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Tagged Image Format file with tick marks as the only annotation.
Without the header file, the tif file can be imported into many
standard graphics programs.  The header file provides geographic
information (geotif) for direct import into ARC/INFO and ARC/VIEW.
The .tfw file must be in the same directory as the .tif file.

mrgtfim.tif and mrgtfim.tfw
-----------------------------------
Color shaded-relief image of the final, merged total-field aeromagnetic data for 
the whole area, without scales or text annotation for import by many graphics 
packages.  When paired with mrgtfim.tfw in the same directory, the file can be 
imported into ARC/INFO and ARC/VIEW.

mrgrtpim.tif and mrgrtpim.tfw
-----------------------------------
Color shaded-relief image of the final, merged, reduced-to-pole aeromagnetic 
data without scales or text annotation for import by many graphics packages.  
When paired with mrgrtpim.tfw in the same directory, the file can be imported 
into ARC/INFO and ARC/VIEW.

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1:175,000 SCALE PDF FILES
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Portable document format of with map and color scales and latitude/longitude labels for Adobe Acrobat Reader, which is available at no charge from www.adobe.com.  Original plots are at 1:175,000 scale, which will give a 30" wide by 44" high plot if no scaling is applied.

mrgtfim.pdf 
-------------
Color shaded-relief image of the final, merged total-field aeromagnetic data for 
the whole area, with annotation for plotting.

mrgrtpim.pdf 
-------------
Color shaded-relief image of the final, merged, reduced-to-pole aeromagnetic 
data, with annotation for plotting.


*Trade names are used for descriptive purposes only.