Thorium content and related data were digitized from radiometric and survey route location maps of western Afghanistan published in 1976. The thorium content data were digitized along contour lines from 33 maps in a series entitled "Map of Thorium Contents of Afghanistan (Western Area)," compiled by V. N. Kirsanov and R. S. Derzhimanov. The survey route location data were digitized along flight-lines located on 33 maps in a series entitled "Survey Routes Location and Contours of Flight Equal Altitudes, Western Area of Afghanistan," compiled by Z. A. Alpatova, V. G. Kurnosov, and F. A. Grebneva.

DATA PRODUCTS

All grids are presented in Geosoft binary grid format, with two files describing each of the grids (suffixes .grd and .gi). All databases are presented in Geosoft database format (suffix .gdb). Either of these formats can be converted to other formats using the free conversion software offered by this company at http://www.geosoft.com/.

1. afghan_Th.gdb - Database of digitized thorium content data.
2. afghan_Th.grd - Grid of digitized thorium content data at 400 m grid spacing.
3. afghan_Th.xyz - ASCII XYZ file of digitized thorium content data.
4. afghan_Th.tif - ArcView GeoTIFF of digitized thorium content data.
5. afghan_Th_text.jpg - Thorium content map legend of Kirsanov and Derzhimanov.
6. 3-33_lines_ln.shp - ArcView Shape file of flight-line locations.
7. readme_thorium_datafiles.pdf - Description of the data products.

PROJECTION SPECIFICATIONS

All databases, maps, grids, and xyz files in this report use the following projection specifications:

• Projection = Transverse Mercator
• Central meridian = 66 degrees E
• Base latitude = 34 degrees N
• Scale factor = 0.9996
• Semi-major ellipsoid axis = 6378137 m
• Eccentricity = 0.08181919084
• Horizontal datum = WGS 84
• Ellipsoid = WGS 84

This web site makes available to users the data products mentioned above for these surveys. To view this directory, click on the link below. To view the README file ("readme_thorium_datafiles.pdf") describing the aeromagnetic data product files, click on the README line following.

Thorium Data Directory

README_thorium_datafiles.pdf file describing data in above directory

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For more information about this report contact: Pat Hill

Version 1.0

Posted March 2007

• Uranium Content Map

• Thorium Content Map

• Potassium Content Map

• Gamma-Ray Intensity Map

• Western Afghanistan Radiometrics

• Metadata TXT file

• Crustal Team