Vast metal reserves lie deep beneath the surface of the Qinghai-Tibet Plateau, according to the first large-scale geological survey of the area.

Officials with the China Geological Survey (CGS) say once exploited, the reserves will greatly relieve the current strain on China's limited resources.

The seven-year survey, results of which were released yesterday by the CGS, was carried out to gauge the area's resources and tourism potential.

It has found more than 600 potential sites for new mines.

It is estimated that the plateau has reserves of 30-40 million tons of copper, 40 million tons of lead and zinc and several billion tons of iron ore.

Notably, a series of rich iron seams were discovered in Nixiong, near the Plateau's center, which offer reserves of up to 500 million tons.

Rich iron ore can be directly refined without prior treatment and so is prized by steel producers.

If proven, the Nixiong rich iron ore seams would be China's first substantial rich iron ore supplies.

The plateau, which straddles six provinces and autonomous regions in southwest China, stands an average of 4300 meters above sea level.

Harsh conditions at that height mean more than half the 2.6 million square kilometre area has yet to be surveyed, said Zhuang Yuxun, director of the Department of Geological Investigation of the CGS.

It took more than 1,000 experts from 24 geological survey teams seven years to come up with the survey's results.

With the help of remote sensing equipment, combined with a lot of hiking, the experts have produced 110 regional geological maps on a 1:250,000 scale. The maps are the first to detail the plateau's mineral resources and potential tourism spots.

"The survey represents an historical step in our understanding of the geology of China," said Zhang Hongtao, deputy director of the CGS.

He noted that most developed countries had completely surveyed their territories to a scale of 1:50,000.

"We will speed up the surveying process to more accurately locate these minerals," said Zhang. "Once mines are developed they will greatly relieve the strain on China's existing resources."

Despite the promise of rich rewards from mining in the area, Zhang called for a gradual development of mining, warning that blind exploitation could permanently damage the plateau's fragile ecosystem.

"We suggest a gradual development, with natural restoration plans drawn up before industrial exploitation begins," he said.

The survey also unearthed thousands of fossilized sea creatures, confirming that the plateau was once sea bed.

Zhang said the fossils could prove invaluable for understanding the area's geological transformation.

The area is currently thought to have been sea bed more than 100 million years ago, which was forced up by upheaval in the earth's crust.

"It is likely that a major theory geo-science breakthrough will come from finds on the plateau," said Li Tingdong, an academician with the Chinese Academy of Sciences.

Editor: Yan