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In geological
terms, the creation of the Himalayas
and the rising of the Tibetan
plateau are extremely recent events.
The mountains originated less than
four million years ago, making them
among the youngest in the world.
About 80 million years ago India
broke away from an early massive
proto continent. Slowly and steadily
it moved across the ancient Sea of
Tethys, collecting hard sheets of
rock along the way. Eventually it
rammed into the soft underside of
Asia, which the rock easily
penetrated and pushed up, creating
the Himalayas. From sea level these
mountains rose rapidly to a height
of nearly 9,000 meters ( 30,000
feet). Today the succession of
parallel ranges, running east to
west for nearly 3,200 kilometers (
2,000 miles), reveals this original
plate boundary between Indian and
Asia. In fact, the movement of
Sub-continental India is still
forcing the Himalayas upwards at a
rate of two centimeters ( 0.8
inches) per year in places.
The rivers of Tibet existed before
the collision of India and Asia. As
the soft sedimentary rocks that
formed the bottom of the Sea of
Tethys were folded up, the rivers
were able to cut through them and
maintain their original
north-to-south course. ( The Yarlong
Tsangpo River is a major exception.)
As a result there are many
spectacular gorges and mountain
ranges sliced up into individual
massifs.
Much of Tibet, once well-forested,
lush and fertile, is today one of
the world's most terrifying,
unforgiving places. As the Himalayas
increased in height, less and less
moisture reached the areas north of
the range. The result has been a
slow botanical death to the great
northern plateau, the
desertification of huge regions of
Tibet and Xinjiang.
There are three distinct
geographical regions in Greater
Tibet. By far the largest natural
region is the northern plateau, of
Chang Tang, an enormous expanse of
over a million square kilometers (
386,000 square miles). The second
main geographical region of Tibet,
the outer plateau, extends in a
great arc for nearly 3,500
kilometers ( 2,200 miles) from
Baltistan in the west to beyond
Xining, the capital of Qinghai, in
the east. And the last not the least
main geographical region is the
southeastern plateau or 'river gorge
country', comprising only one-tenth
of the total area of Tibet. Plant
and animal life here is vastly
richer than in the other regions.
Forest are very much a
characteristic of the southeastern
plateau; its western and northern
boundaries follow the natural limits
of trees.
Shannan located to the south of
Gangtise ranges, altitude 3500
meters, average temperature 10?,
cover an area of 7.35 square km with
a population of more than 290,000,
with its unique and marvellous
historical culture, pure and
Fascinating folklore customs,
miraculous and charming natural
scenes. Shannan always enjoys the
high fame of " The roof of Tibetan
People, The Cradle of The Tibetan
Civilization" which is only in
Tibet, and is the focus of the
world's attention.
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