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(Xinhua)
Updated: 2007-10-11 20:53

URUMQI -- Chinese topographers on Wednesday began surveying nearly 20,000 square kilometers of land that remained unmapped for nearly 60 years in northwestern Xinjiang Uygur Autonomous Region.

The mapping will cover the Lop Nur Depression, Kumtag Desert and Altun Mountain in southeastern Xinjiang, mostly desert, and is expected to produce a map with a 1:50,000 scale, a benchmark for a standard topographical map, said Liu Geqing, an official with the Xinjiang Bureau of Surveying and Mapping, which is in charge of the project.

"The project will draw a clear picture of the various natural resources in this region and provide geological information for the ecological preservation and scientific planning," said Sun Di, a topographer of the Xinjiang bureau.

Due to technological reasons, about 2.02 million square kilometers of land in China, approximately 20 percent of its territory, have not been mapped since 1949 when the New China was founded.