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Desert Extraction: Earth Image of the Week June 24, 2011
Satellite image of remote Chinese facility.
The discovery of potash at Lop Nur in the mid-1990s turned the area into a large-scale mining operation.
Humans are able to transform the planet in some of the most inhospitable environments. Such is especially the case in northwest China’s Lop Nur region.

Here, at the eastern end of the Taklimakan Desert, advancing sand dunes can tower up to 650 feet in height.

Blinding sandstorms often rage across the landscape, which is rich in potash, a potasium salt that is a key ingredient in fertilizer.

Despite the harsh conditions, Chinese engineers have been able to construct a vast facility to extract the plant nutrient for use in farmland located in far more lush environments.

The image of the plant to the right was captured on May 17, 2011, by the Advanced Land Imager on NASA’s Earth Observing-1 satellite.

Large evaporation ponds to extract the potash can clearly be seen. The aqua and green tones of the plant are contrasted by the browns and tans of the surrounding desert sands.

Lop Nur was not always such a wind-swept wasteland. During the early and middle Pleistocene epoch, the area held a large brackish lake. Uplift of the northern part of the lake in the late Pleistocene created hollows that became receptacles for potash deposition.

The main potash deposits found at Lop Nur today are brine potash, and this site is the second-largest source of potash in China.

Examination of plant and mollusk remains at the lake, as well as studies of sediments, indicate that the Lop Nur region experienced a severe drought about 3,000 years ago, followed by wetter conditions.

Between 1,250 and 400 years ago, Lop Nur probably experienced conditions favorable to farming and settlement, with red willow trees growing in the area. Pottery relics dating from the Tang and Song dynasties further testify to the welcoming conditions at the lake centuries ago.

But starting around 400 years ago, a more arid climate emerged, completely drying out Lop Nur.

Full story and image: NASA