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.
Bian is taking part in a month-long scientific expedition to the
Himalayas.
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
meters.
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 meters, 3.70 meters 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.
Other scientists argue that if the range grows horizontally, a
huge graben a basin formed between parallel fault lines will be
formed somewhere on the plateau. They believe that as the collision
of continents continues, the altitude of the Qinghai-Tibet Plateau
and the Himalayas will continue to increase.
(China Daily October 20, 2006)