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In May 2009, AAAS reviewed satellite imagery of the Sheberghan area of northern Afghanistan, where
possible mass graves were suspected of being created in 2001. Imagery from 2006-2007 reveals
two large pits, possibly comprising the graves, being excavated over a series of months in this area. An August 2006 image shows two
possible vehicles present at the site of one pit. These vehicles fit the dimensions of a
hydraulic excavator and a dump truck, which may have aided in the excavation of the pits. Based
on these findings and the investigation of Physicians for Human Rights, which first approached
AAAS with this project, the Obama administration has ordered a US government review of the
incident at Dasht-e-Leili.
In May of 2009 the Science and Human Rights Program of the American Association for the
Advancement of Science (AAAS) undertook a review of satellite imagery acquired of the
Sheberghan area in the Jowzjan Province of northern Afghanistan (Figure One). This review
was done at the request of Physicians for
Human Rights (PHR), who asked AAAS to provide satellite imagery analysis for their
investigation of possible mass graves at Dasht-e-Leili, near Sheberghan. According to PHR,
the graves had reportedly been created in 2001. Then, at some point prior to July, 2008,
two large pits were dug in the area and the fill taken away. Hoping to clarify the
excavation date, PHR requested that AAAS research and acquire available satellite imagery
of the area to determine when two of the sizeable pits possibly comprising the graves
might have first appeared.
Figure One: Sheberghan, Afghanistan
Since 2000, high-resolution commercial satellite operators have acquired imagery, largely
for areas where customers request images. Once imagery is acquired from a satellite, it is
then added to the companies' archives and generally made available for resale. Based on
the information about the location of the purported graves provided by PHR, AAAS searched
these archives for available imagery, ultimately utilizing several sources.
One source was the Ikonos satellite, operated by the
GeoEye company. Ikonos has a multispectral sensor with one meter panchromatic
resolution and has been in operation since 1999. Ikonos provided an image of the site
dated May 12, 2000. Another satellite utilized was QuickBird, operated by DigitalGlobe, which has 60 centimeter panchromatic
resolution. QuickBird became operational in 2002 and provided the bulk of the images used
in this project, acquired on July 2, 2004, August 5, 2006, and October 24, 2007.
Finally, two lower resolution satellites also contributed imagery to this analysis.
Specifically, the British research satellite
TopSat, with two meter resolution, provided an image from January 27, 2007. In
addition, the French SPOT-5 satellite, operated by Spot
Image, provided an image with 2.5 meter resolution, acquired on May 8, 2007. Though
the SPOT and TopSat images are of lower resolution and barely indicate the presence of the
pits, they did provide confirmation of their existence during this research activity and
led to acquisition of further imagery.
Using coordinates provided by PHR (36.65° latitude, 65.70° longitude), AAAS located and analyzed multiple images of the site acquired by
the QuickBird, Ikonos, TopSat, and SPOT-5 satellites. A QuickBird image from 2004 indicates no pits present (Figure Two). Another QuickBird
image from August 5, 2006 indicates one of the pits present, and two possible vehicles atop the site of what develops into the second pit
(Figure Three). While it is impossible to positively identify the two vehicles, their dimensions and appearance are consistent with the
dimensions of a truck and a hydraulic excavator (Figure Four). To determine this, AAAS compared the dimensions of the possible excavator with the boom length,
track length and transport width of known excavators produced by companies like Caterpillar and Volvo. To determine the heights of the
vehicles, AAAS used the equation:
L * tan(θ) = H
, where L is the length of the vehicle shadow, θ is
the angle of the sun relative to the ground, and H is the vehicle height. L was determined via the measure tool in ESRI's ArcMap, while
θ (also known as the sun elevation angle) was provided in the metadata of the acquired satellite images. These efforts helped determine whether the
vehicles were likely to be a dump truck and hydraulic excavator. Finally, a lower resolution TopSat image from January 29, 2007, indicates both pits are
present, and a high-resolution image of them was acquired by QuickBird on October 24, 2007 (Figure Five). Results are summarized in Table
One below:
| Table One: Summary of Imagery Results |
| Satellite |
Image Date |
Results |
| QuickBird |
07/02/2004 |
No pits visible (Figure Two) |
| QuickBird |
08/05/2006 |
One pit present; possible excavation vehicles visible (Figures Three and Four) |
| SPOT-5 |
05/08/2007 |
Two pits visible (lower resolution) |
| TopSat |
01/27/2007 |
Two pits visible (lower resolution) |
| QuickBird |
10/24/2007 |
Two pits visible (Figure Five) |
Samples of the imagery are available as a Google Earth layer via this link. A full description of all imagery analyzed in this study is provided below. Note
that not all images analyzed are reproduced in this report.
Figure Two: Possible Grave Site
July 2, 2004 |
Figure Three: Possible Grave Site
August 5, 2006 |
 |
 |
| © 2009 DigitalGlobe |
© 2009 DigitalGlobe |
The image on the left shows the Dasht-e-Leili site on July 2, 2004, and indicates
no open pits visible. The image on the right shows the Dasht-e-Leili site on August 5,
2006, and indicates one open pit visible, with two likely vehicles atop the area which
would become the second pit. For a close-up of the possible vehicles, see Figure Four.
Figure Four: Vehicles at Possible Grave Site, August 5, 2006
 |
 |
| © 2009 DigitalGlobe |
© 2009 DigitalGlobe |
This image show a close-up of the vehicles shown in Figure Three, unannotated on the
left sample and with dimensions indicated on the right sample. The top-most vehicle, a
possible truck, has a height estimated at 3.25 meters, based on the extent of the shadow.
The bottom vehicle could be a hydraulic excavator, and a survey of hydraulic excavator
dimensions indicate track lengths between 3.49 and 4.46 meters, and track widths between
2.59 and 3.19 meters.
A survey was undertaken to determine whether the
shape of the suspected vehicle in the August 5, 2006 image was similar to that of a hydraulic excavator. Table Two below provides the dimensions of hydraulic excavators. The table lists
the length of the tracks upon which the cabin sits, the width of each excavator, and the combined length of the boom and
arm (or stick). A diagram of a typical excavator may be found here. The combined boom and arm length is only possible when the mechanism is fully extended. The August 5, 2006
image, however, is likely less than fully extended, and therefore, the estimate of 6.9 meters in Figure Four
underestimates the combined boom and arm length.
| Table Two: Sample Hydraulic Excavator Dimensions |
| Manufacturer |
Model |
Track Length (m) |
Transport Width (m) |
Boom + Arm Length (m) |
| Caterpillar |
311D LRR |
3.49 |
2.69 |
6.9 |
|
314D CR |
3.49 |
2.59 |
7.45 |
|
315D L |
3.97 |
2.59 |
7.7 |
|
320D L |
4.08 |
3.08 |
8.58 |
| Volvo |
EC160C |
3.98 |
2.59 |
7.5 |
|
EC210C |
4.46 |
3.19 |
8.2 |
|
ECR325C |
4.46 |
3.09 |
8.2 |
Figure Five: Suspected Grave Site, October 24, 2007
 |
| © 2009 DigitalGlobe |
This image shows the Dasht-e-Leili site on October 24, 2007, with both open pits
visible.
Based on coordinates provided by Physicians for Human Rights, AAAS analyzed a series of images related to the Dasht-e
Leili graves. The progression of images shows two possible gravesites being excavated in close proximity to one
another. In addition, an image from August 5, 2006 may show a hydraulic excavator and dump truck. These vehicles may
have facilitated the excavation of the possible gravesites. Based on these findings and the investigation of Physicians
for Human Rights, which first approached AAAS with this project, the Obama administration has ordered a US
government review of the incident at Dasht-e-Leili.
- A Google Earth layer of the imagery from this study is available
here.
- Physicians for Human Rights maintains a site devoted to the Dasht-e Leili mass
graves here.
- Based on the years-long investigation by Physicians for Human Rights and imagery from
this study, the Obama administration pledged to investigate the events of Dasht-e Leili.
News coverage of this report can be found here.
(case study posted July 14, 2009)
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