The Himalayas: Two continents
collide
Among the most dramatic and
visible creations of plate-tectonic forces are the lofty Himalayas, which
stretch 2,900 km along the border between India and Tibet. This immense
mountain range began to form between 40 and 50 million years ago, when
two large landmasses, India and Eurasia, driven by plate movement, collided.
Because both these continental landmasses have about the same rock density,
one plate could not be subducted under the other. The pressure of the impinging
plates could only be relieved by thrusting skyward, contorting the collision
zone, and forming the jagged Himalayan peaks.
About 225 million years ago,
India was a large island still situated off the Australian coast, and a
vast ocean (called Tethys Sea) separated India from the Asian continent.
When Pangaea broke apart about 200 million years ago, India began to forge
northward. By studying the history -- and ultimately the closing-- of the
Tethys, scientists have reconstructed India's northward journey. About
80 million years ago, India was located roughly 6,400 km south of the Asian
continent, moving northward at a rate of about 9 m a century. When India
rammed into Asia about 40 to 50 million years ago, its northward advance
slowed by about half. The collision and associated decrease in the rate
of plate movement are interpreted to mark the beginning of the rapid uplift
of the Himalayas
The 6,000-km-plus journey
of the India landmass (Indian Plate) before its collision with Asia (Eurasian
Plate) about 40 to 50 million years ago (see text). India was once situated
well south of the Equator, near the continent of Australia.
The Himalayas and the Tibetan
Plateau to the north have risen very rapidly. In just 50 million years,
peaks such as Mt. Everest have risen to heights of more than 9 km. The
impinging of the two landmasses has yet to end. The Himalayas continue
to rise more than 1 cm a year -- a growth rate of 10 km in a million years!
If that is so, why aren't the Himalayas even higher? Scientists believe
that the Eurasian Plate may now be stretching out rather than thrusting
up, and such stretching would result in some subsidence due to gravity
Fifty kilometers north of
Lhasa (the capital of Tibet), scientists found layers of pink sandstone
containing grains of magnetic minerals (magnetite) that have recorded the
pattern of the Earth's flip-flopping magnetic field. These sandstones also
contain plant and animal fossils that were deposited when the Tethys Sea
periodically flooded the region. The study of these fossils has revealed
not only their geologic age but also the type of environment and climate
in which they formed. For example, such studies indicate that the fossils
lived under a relatively mild, wet environment about 105 million years
ago, when Tibet was closer to the equator. Today, Tibet's climate is much
more arid, reflecting the region's uplift and northward shift of nearly
2,000 km. Fossils found in the sandstone layers offer dramatic evidence
of the climate change in the Tibetan region due to plate movement over
the past 100 million years.
At present, the movement
of India continues to put enormous pressure on the Asian continent, and
Tibet in turn presses on the landmass to the north that is hemming it in.
The net effect of plate-tectonics forces acting on this geologically complicated
region is to squeeze parts of Asia eastward toward the Pacific Ocean. One
serious consequence of these processes is a deadly "domino" effect: tremendous
stresses build up within the Earth's crust, which are relieved periodically
by earthquakes along the numerous faults that scar the landscape. Some
of the world's most destructive earthquakes in history are related to continuing
tectonic processes that began some 50 million years ago when the Indian
and Eurasian continents first met.
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The Himalaya is a mountain
range in Asia, separating the Indian subcontinent from the Tibetan Plateau.
By extension, it is also the name of the massive mountain system which
includes the Himalaya proper, the Karakoram, the Hindu Kush, and a host
of minor ranges extending from the Pamir Knot. The name is from Sanskrit
himalaya, a tatpurusa compound meaning "the abode of snow" (from hima "snow",
and alaya "abode"; see also Himavat).
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Together, the Himalaya mountain
system is the planet's highest and home to all fourteen of the world's
highest peaks: the Eight-thousanders, including Mount Everest. To comprehend
the enormous scale of Himalaya peaks, consider that Aconcagua, in the Andes,
at 6,962 m, is the highest peak outside the Himalaya, while the Himalaya
system has over 100 separate mountains exceeding 7,200 m.
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The Himalaya stretches across
five nations: Bhutan, China, India, Nepal, and Pakistan. It is the source
of three of the world's major river systems, the Indus Basin, the Ganga-Brahmaputra
Basin and the Yangtze Basin. An estimated 750 million people live in the
watershed area of the Himalayan rivers, which also includes Bangladesh
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The Indian Himalayas
The arc-shaped Himalayas
extend along the entire northern boundary of India and carve just as far
across the Indian subcontinent as they do deeply into the life around them.
The term "Himalaya" -- a Sanskrit word meaning "the Abode of Snow" -- was
coined by the Indian pilgrims who traveled in these mountains in ancient
times. For centuries, the inhabitants of India have been fascinated by
this mountain chain. The feeling is a mixture of admiration, awe and fear;
and for the Hindus of India, the Himalayas are also "the Abode of God".
There are numerous pilgrim routes that have brought the Hindu pilgrims
to these mountains since time immemorial. The Indian Himalayas cover a
vast area along the northern frontiers of the country and span five Indian
States -- Jammu and Kashmir , Himachal Pradesh, Uttar Pradesh, Sikkim and
Arunachal Pradesh -- from west to east. For the mountain people living
in these states, the Himalayas continue to be the predominant factor in
their lives. Having acted as a natural and political barrier for centuries,
the Himalayas have isolated a number of communities, cultures and customs.
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The Indian Himalayas mark
the crossroads of Asia's three main religions. Kashmir -- formerly a paradise
on earth -- is largely influenced by Islam. The foothills of Jammu, Himachal
Pradesh and Uttar Pradesh form the northern boundary of Hinduism. The entire
Trans Himalayan region, from Ladakh (Jammu and Kashmir) through Tibet and
onto the eastern state of Sikkim, has seen a dominating influence of Buddhism.
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Nepal Himalayas
General info
Containing nine of the world's
fourteen highest mountain peaks, Nepal is a true Himalayan kingdom. The
Himalayas cover three fourths of the land in Nepal. It is home to some
of the highest, remotest, most rugged and most difficult terrain in the
world. The loftiest peak in the world -- Mount Everest -- and other high
peaks like Lhotse, Nuptse, Annapurna, Dhaulagiri and Manaslu, plus the
presence of some exquisitely beautiful trekking routes, attract hundreds
of thousands of people from all over the world to this lovely Himalayan
destination.
The country of Nepal can
be divided into three parallel bands running from the northeast towards
the southwest. Along the north of Nepal runs the Great Himalayan Range,
the highest mountain range in the Himalayan system. This range has an average
altitude of about 4,570 m (about 15,000 ft) and remains perpetually snow-covered.
On this range rise some of the loftiest mountain peaks in the world --
Mount Everest, Kanchenjunga, Lhotse, Makalu, Cho Oyu, Dhaulagiri, Manaslu,
and Annapurna.
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Further south runs a complex
system of intermediate ranges at an altitude of 8,000-14,000 ft. Prominent
ranges in this mountain system include the Mahabharat and Churia ranges.
High mountain ranges are interspersed with broad inhabited river valleys.
The third and southernmost region is the Terai, a swampy terrain which
is the northern extension of the Indian plains.
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Leh
Ladakh With Gallery
Tibetan Himalayas
General info
Tibet is situated on the
Qingzang (Qinghai-Tibet) Plateau. This is the highest plateau in the world
with an average elevation of 4,875 m (more than 16,000 ft), and the Tibetan
Plateau is also called the Roof of the World. In 1964, Tibet became an
Autonomous Region of China. It is surrounded in the north and east by other
provinces of China, in the south and west by Burma, India, Bhutan, and
Nepal. The capital of Tibet is Lhasa.
Tibet is surrounded on three
sides by vast mountain systems: the Kunlun mountains of Central Asia in
the north, the Karakoram range in the west and the Himalayas in the south
Trans Himalayas
Tibet lies in a region known
as Trans Himalayas. As the term suggests, Tibet lies beyond the main Himalayan
range. The Trans Himalayan region itself is an ill-defined mountain region
covering an area of about 1,000 km (600 miles) and having a width ranging
from 225 km (140 miles) to about 32 km (20 miles). Unlike the main Himalayas,
the Trans Himalayan mountains are not divided by deep river gorges. On
the Roof of the World, passes average 5,330 m (17,500 ft) in height, with
the highest being the Chargoding Pass at a height of 5,885 m (19,308 ft).The
first recorded European exploration of the Trans Himalayas was carried
out by the Swedish explorer Sven Hedin. Hedin explored Tibet and the Xinjiang
(Sinkiang) region extensively. He identified the sources of the Brahmaputra,
Indus, and Satluj rivers, and, in 1906, explored and named the Kailas Range
The southern part of Tibet falls within the Himalayan region. Some of the
world's highest mountains define the southern border of Tibet. These include
Mt Everest (8,848 m) -- the highest mountain in the world, Namcha Barwa
(7,756 m / 25,445 ft) -- around which the Brahmaputra carves a fantastic
gorge to enter India, and Gurla Mandhata (7,728 m / 25,355 ft). Running
north of the main Himalayan range is the Kailas Range, named thus by Hedin.Between
the two ranges lies the river valley region extending for about 1,000 km
from west to east. The Brahmaputra River (known in Tibet as the Yarlung
Tsangpo) flows from west to east through most of this region. The Tibetan
plateau is the source of some of the biggest rivers in the Himalayas. The
Brahmaputra, Indus and Satluj are three Trans Himalayan rivers that originate
in Tibet, cut across the main Himalayas making fearsome gorges and then
flow towards the plains.
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