Local-Area-Enhanced, 2.5-Meter Resolution Natural-Color and 
  Color-Infrared Satellite-Image Mosaics of the Parwan 
  Mineral District in Afghanistan

  By Philip A. Davis

  Data Series 709-CC

  2013

  U.S. Department of the Interior
  U.S. Geological Survey


  Abstract:

  The U.S. Geological Survey (USGS), in cooperation with the 
  U.S. Department of Defense Task Force for Business and 
  Stability Operations, prepared databases for mineral-
  resource target areas in Afghanistan. The purpose of the 
  databases is to (1) provide useful data to ground-survey 
  crews for use in performing detailed assessments of the 
  areas and (2) provide useful information to private 
  investors who are considering investment in a particular 
  area for development of its natural resources. The set of 
  satellite-image mosaics provided in this Data Series (DS) 
  is one such database. Although airborne digital color-
  infrared imagery was acquired for parts of Afghanistan in 
  2006, the image data have radiometric variations that 
  preclude their use in creating a consistent image mosaic 
  for geologic analysis. Consequently, image mosaics were 
  created using ALOS (Advanced Land Observation Satellite; 
  renamed Daichi) satellite images, whose radiometry has been 
  well determined (Saunier, 2007a,b). This part of the DS 
  consists of the locally enhanced ALOS image mosaics for the 
  Parwan mineral district, which has gold and copper 
  deposits.

  ALOS was launched on January 24, 2006, and provides 
  multispectral images from the AVNIR (Advanced Visible and 
  Near-Infrared Radiometer) sensor in blue (420-500 
  nanometer, nm), green (520-600 nm), red (610-690 nm), and 
  near-infrared (760-890 nm) wavelength bands with an 8-bit 
  dynamic range and a 10-meter (m) ground resolution. The 
  satellite also provides a panchromatic band image from the 
  PRISM (Panchromatic Remote-sensing Instrument for Stereo 
  Mapping) sensor (520-770 nm) with the same dynamic range 
  but a 2.5-m ground resolution. The image products in this 
  DS incorporate copyrighted data provided by the Japan 
  Aerospace Exploration Agency ((c)JAXA,2006, 2007), but the 
  image processing has altered the original pixel structure 
  and all image values of the JAXA ALOS data, such that 
  original image values cannot be recreated from this DS. As 
  such, the DS products match JAXA criteria for value added 
  products, which are not copyrighted, according to the ALOS 
  end-user license agreement.

  The selection criteria for the satellite imagery used in 
  our mosaics were images having (1) the highest solar-
  elevation angles (near summer solstice) and (2) the least 
  cloud, cloud-shadow, and snow cover. The multispectral and 
  panchromatic data were orthorectified with ALOS satellite 
  ephemeris data, a process which is not as accurate as 
  orthorectification using digital elevation models (DEMs); 
  however, the ALOS processing center did not have a precise 
  DEM. As a result, the multispectral and panchromatic image 
  pairs were generally not well registered to the surface and 
  not coregistered well enough to perform resolution 
  enhancement on the multispectral data. Therefore, it was 
  necessary to (1) register the 10-m AVNIR multispectral 
  imagery to a well-controlled Landsat image base, (2) mosaic 
  the individual multispectral images into a single image of 
  the entire area of interest, (3) register each panchromatic 
  image to the registered multispectral image base, and (4) 
  mosaic the individual panchromatic images into a single 
  image of the entire area of interest. The two image-
  registration steps were facilitated using an automated 
  control-point algorithm developed by the USGS that allows 
  image coregistration to within one picture element. Before 
  rectification, the multispectral and panchromatic images 
  were converted to radiance values and then to relative-
  reflectance values using the methods described in Davis 
  (2006). Mosaicking the multispectral or panchromatic images 
  started with the image with the highest sun-elevation angle 
  and the least atmospheric scattering, which was treated as 
  the standard image. The band-reflectance values of all 
  other multispectral or panchromatic images within the area 
  were sequentially adjusted to that of the standard image by 
  determining band-reflectance correspondence between 
  overlapping images using linear least-squares analysis. The 
  resolution of the multispectral image mosaic was then 
  increased to that of the panchromatic image mosaic using 
  the SPARKLE logic, which is described in Davis (2006). Each 
  of the four-band images within the resolution-enhanced 
  image mosaic was individually subjected to a local-area 
  histogram stretch algorithm (described in Davis, 2007), 
  which stretches each band's picture element based on the 
  digital values of all picture elements within a 500-m 
  radius. The final databases, which are provided in this DS, 
  are three-band, color-composite images of the local-area-
  enhanced, natural-color data (the blue, green, and red 
  wavelength bands) and color-infrared data (the green, red, 
  and near-infrared wavelength bands).

  All image data were initially projected and maintained in 
  Universal Transverse Mercator (UTM) map projection using 
  the target area's local zone (42 for Parwan) and the WGS84 
  datum. The final image mosaics were subdivided into two 
  overlapping tiles or quadrants because of the large size of 
  the target area. The two image tiles (or quadrants) for the 
  North Bamyan area are provided as embedded geotiff images, 
  which can be read and used by most geographic information 
  system (GIS) and image-processing software. The tiff world 
  files (tfw) are provided, even though they are generally 
  not needed for most software to read an embedded geotiff 
  image.

  Disclaimer:

  Although these data have been processed successfully on a 
  computer system at the U.S. Geological Survey, no warranty 
  expressed or implied is made regarding the display or 
  utility of the data on any other system, or for general or 
  scientific purposes, nor shall the act of distribution 
  constitute any such warranty. The U.S. Geological Survey 
  shall not be held liable for improper or incorrect use of 
  the data described and (or) contained herein.

  Contact Information:

  If you have any questions regarding this dataset please 
  feel free to contact:
  Philip A. Davis, Research Geologist
  U.S. Geological Survey
  2255 North Gemini Drive, Building 4
  Flagstaff, AZ 86001
  pdavis@usgs.gov
  (928) 556-7084

  ----------------------------------------------------
  This Data Series includes the following Information. 
  ----------------------------------------------------

  DIRECTORY

  index_maps

  Parwan_Area-of-Interest_Index_Map.pdf -- Index map stored 
  in Adobe Acrobat (PDF) format displaying the location of 
  the Parwan mineral district within Afghanistan in the 
  geographic coordinate system. Index map is also provided in 
  jpeg format.

  Parwan_Image_Index_Map.pdf -- Index map of the image 
  products showing the extent of the target area and tile or 
  quadrant scheme that was used to subdivide the image 
  mosaics for the target area. This information is displayed 
  on the topographic shaded-relief base map of Bohannon 
  (2007) in the UTM map projection and stored in both PDF and 
  jpeg formats.

  image_files

  Local-area-enhanced, 2.5-m natural-color and color-infrared 
  satellite-image mosaics in geotiff format with their tfw 
  files. All images with their tfw and metadata files are 
  compressed with standard file compression software to 
  facilitate file transfer.

  metadata

  PARWAN_UTM_WGS84_Z42_NC_Qx.tif.txt -- FGDC compliant 
  metadata files for each image tile or quadrant (designated 
  by Qx). NC designates natural-color image data.

  PARWAN_UTM_WGS84_Z42_CIR_Qx.tif.txt -- FGDC compliant 
  metadata files for each image tile or quadrant (designated 
  by Qx). CIR designates color-infrared image data.

  shapefiles

  Parwan_Image_Mosaic_Index.shp -- A shapefile showing the 
  boundary for the area of interest.

  index.html -- http://pubs.usgs.gov/ds/709/cc/

  1_readme.txt -- This file.

  References Cited:

  Bohannon, R.G., 2007, Topographic map of quadrangle 3568, 
  Polekhomri (503) and Charikar (504) quadrangles, 
  Afghanistan: U.S. Geological Survey Open-File Report 2005-
  1101-B, 1:250,000 scale, available at 
  http://pubs.usgs.gov/of/2005/1101/B/.

  Davis, P.A., 2006, Calibrated Landsat ETM+ nonthermal-band 
  image mosaics of Afghanistan: U.S. Geological Survey Open-
  File Report 2006-1345, 18 p., available at 
  http://pubs.usgs.gov/of/2006/1345/.

  Davis, P.A., 2007, Landsat ETM+ false-color image mosaics 
  of Afghanistan: U.S. Geological Survey Open-File Report 
  2007-1029, 22 p., available at 
  http://pubs.usgs.gov/of/2007/1029/.

  Saunier, S., 2007a, Final calibration/validation report, 
  PRISM: GAEL Consultant report, 27 p., accessed April 23, 
  2012, at http://earth.esa.int/pub/ESA_DOC/ALOS011.pdf.

  Saunier, S., 2007b, Final calibration/validation report, 
  AVNIR-2: GAEL Consultant report, 25 p., accessed April 23, 
  2012, at http://earth.esa.int/pub/ESA_DOC/ALOS012.pdf.