Afghanistan's potential wealth has long been studied with interest by its ruling powers. The first scientific exploration of the land came with British invasions in 1839 and 1878, and the first systematic surveying efforts began in the mid-20th century, when French, German, Italian and Soviet geologists, at the invitation of King Zahir Shah, traveled the nation on foot and donkey-back, taking rock samples by hand. It was the Soviet invaders, though, who conducted what remain the most extensive ground surveys: They used drilling, trenching, and field samples to evaluate 20 sites in detail, paying special attention to the large Aynak copper deposit south of Kabul and the even larger Hajigak iron deposit in the Hindu Kush. After the Soviet withdrawal in 1989, all geological work came to a halt. In 1995, as the Taliban massed on the outskirts of Kabul, the staff of the AGS did manage to compile most of the previous research, and when the Taliban took Kabul a year later, the staff hid the documentation in their homes, where it remained until the current occupation.
Still, significant areas of the country had yet to be studied. A team of USGS geologists delivered a briefing in Kabul to the staff of then-ambassador Zalmay Khalilzad, with a particular focus on the petroleum-producing potential of the Sheberghan region in the north. The ambassador’s staff, however, was more interested in knowing if there might be undiscovered wealth in areas that were seen as susceptible to Taliban influence. “The question was: Is there any potential for oil and gas in the southern part of the country? Because that would be critical,” recalls Medlin, the USGS geologist. The presence of natural wealth, it was thought, could attract large-scale development that, in addition to growing the national economy and enhancing the authority of the central government, might employ the people of that unstable region in something other than insurgency.
The answer was air power. But remote sensing, no matter how sophisticated, would still present major obstacles. The first was that no private surveyors were willing to risk their crews or equipment in a war zone. The solution: The USGS subcontracted the fieldwork to the U.S. Naval Research Laboratory and NASA.
The survey began with a series of flights by geologists in a Navy NP-3D Orion equipped with dual gravimeters and a magnetometer. Security was always a concern, especially given that the CIA, in the 1980s, had equipped Afghan insurgents with hundreds of surface-to-air missiles to use against the Soviet army. The Department of Defense required the pilots to fly at a standoff distance of at least 12,000 feet vertically aboveground and horizontally away from nearby mountain ranges. Since specialized survival gear would have been required for the crew to go more than 26,000 feet above sea level, the surveyors were not able to examine the 30 percent of the country that was more than 14,000 feet above sea level. It also meant that the survey results were less detailed. “You want to go lower and slower,” Medlin says. “Ideally less than 3,000 feet.”
For the second part of the survey, completed in October 2007, Air Force and NASA pilots crisscrossed the country at 50,000 feet in a modified WB-57 Canberra jet bomber equipped with a hyperspectral 3-D-mapping sensor. The USGS geologists complemented this overflight data with images from the NASA-run LANDSAT and Japanese-run ALOS satellite systems, and also with a series of radar surveys from a space shuttle mission in 2000.
In the end, the USGS remote-sensing project helped to confirm and expand on the older data. It indicated that the Hajigak iron deposit was much larger than previously believed and further suggested the presence of oil and gas deposits in southern and southeastern Afghanistan. But remote surveys can only tell you so much. The WB-57 Canberra sensor, for instance, could only create images with a resolution in which each pixel represented a square about 50 feet across—sharp enough to pick up useful data patterns, but still at best merely suggestive.
Ultimately, understanding which minerals are present in what concentrations in Afghanistan will require field research. Medlin says the USGS is hoping that Afghan geologists will one day be able to do that work themselves. “We are training them,” he adds, “because they are the ones who can get out into the countryside.”single page
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