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A picture of Mount Qomolangma.
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Will the Himalaya Mountains, home to the world's highest peaks, continue to push up into the sky in future? Some Chinese scientists say no.
The Himalayas may have reached their highest altitude and in the centuries to come may even shrink a little, said Bian Qiantao, a researcher with the Institute of Geology and Geophysics of the Chinese Academy of Sciences.
Located on the southern rim of the Qinghai-Tibet Plateau, the Himalaya Mountains form an arc protruding southward. The main part of the range lies in China. "Himalaya" means "abode of snow" in Tibetan. The average height of these mountains is more than 6,000 metres.
Scientists believe that 65 million years ago, the Indian Plate moving north collided with the Eurasian Plate , and the upheaval saw the emergence of the Qinghai-Tibet Plateau as well as the Himalayas.
"Friction between the tectonic plates continues to this day, gradually pushing the Himalayas upward," said Bian.
"But at the same time, a horizontal pulling power inside the lower continental crust and mantle of the earth counteracts this upward movement," said Bian.
According to measurements made by scientists in 2005, the altitude of Mount Qomolangma is 8844.43 metres, 3.70 metres lower than the figure obtained in 1975.
The result suggests that the Himalayas and the Qinghai-Tibet Plateau will not continue to move up indefinitely. After growing to a certain height, the effect of gravity and collision-generated extrusion will make them grow wider, but not higher, Bian said.
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拥有世界最高峰的喜马拉雅山还将继续“长高”吗？我国一些科学家认为“不会”。
中科院地质与地球物理研究院的研究员边千韬说，喜马拉雅山已基本达到最高点，在未来几个世纪内，甚至可能会有所下降。
喜马拉雅山位于青藏高原南侧，呈向南突出的弧形，山脉的主要部分位于中国境内。“喜马拉雅”在藏语中是“冰雪之乡”的意思。喜马拉雅山的平均高度在6000米以上。
科学界普遍认为，青藏高原和喜马拉雅山是6500万年前向北漂移的印度板块与欧亚板块相撞而形成的。
边教授说：“这两个板块之间的摩擦仍在继续，在这种力量的作用下，喜马拉雅山一直在慢慢升高。”
“但同时，从下地壳一直到地幔上部在产生一种东西拉张的力量，这种拉力对喜马拉雅山的继续升高起到了阻碍作用。”
2005年，科学家测出珠穆朗玛峰的海拔为8844.43米，比1975年低3.7米。
测量结果表明，喜马拉雅山和青藏高原不会无限升高。边教授说，喜马拉雅山达到一定高度后，在重力和由板块碰撞产生的挤压力的作用下，山脉会向外扩展，而不会持续增高。
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发布日期：2006-10-24 来源：China Daily
