The Qinghai-Tibet Plateau, dubbed "the roof of the world", is moving northward and eastward at seven to 30 millimeters a year, a Chinese researcher announced Tuesday.
"The plateau is moving because it's being pushed by the Indian plate," said Dr. Tan Kai, a researcher with China Seismological Bureau who is collecting data for a global positioning system (GPS) survey in the towering Kunlun Mountains in Golmud city of northwest China'inghai Province.
Dr. Tan and his colleagues have found through the survey that Lhasa, on the southern end of the plateau, is moving 30 millimeters a year northeast at an angle of 38 degrees. Meanwhile, the Kunlun Mountains in the central plateau is moving 21 millimeters a year at 61 degrees. The Qilian Mountains further north is moving between seven and 14 millimeters a year, at an angle of 80 degrees.
"Which means the entire plateau is moving seven to 30 millimeters a year on average," Tan told Xinhua. "Such moves are barely noticeable and will not change the Chinese continental plate any time soon. But they're still significant from the geological point of view."
The seismological bureau has conducted more than 50 GPS surveys on the roof of the world since 1991. Of the country's 1,056 survey stations, 340 are in the plateau region, which is known as the "third polar of the earth".
Dr. Tan said the GSP surveys can capture real-time, highly precise data to calculate velocity of the crustal movement. Results of the surveys will help scientists study the formation and evolution of the plateau and evaluate the region's risk of earthquake and other geological disasters.
The conclusion was echoed by Fang Xiaomin, a researcher at the Chinese Academy of Sciences Institute of Tibetan Plateau Research.
A collision between the Indian Plate and the Eurasia Continent Plate 40 million years ago shaped the Qinghai-Tibet Plateau and its surrounding geological features, said Fang.
As the two plates of the earth's crust still collide, the plateau is moving north by more than 20 millimeters and is growing taller by several millimeters a year, too, according to Fang.
(Xinhua News Agency August 17, 2005)
