world, with 30 peaks over 24,000 feet. The highest mountains in
Europe, Northand South America barely top 20,000 feet. The word
Himalaya is Sanskrit for"abode of the snow" and a Himal is a massif of
mountains. Technically Himalaya is the plural of Himal and there
should be no such word as Himalayas.
The Himalayas stretch for 1,500 miles from eastern Tibet and China to
a point where India, Pakistan, China and Afghanistan all come
together. The mountain kingdoms of Sikkim, Bhutan and Nepal are all
contained within therange. The southern side ofthe Himalayas are like
a huge climatic wall. During the summer monsoon winds push massive
rain clouds against the mountains squeezing out rain onto some of the
wettest places on earth. Onthe leeward, rain-blocked side of the
range, on the Tibetan plateau, are some of the driest and most barren
places on the planet.
The Himalaya-Karakoram range contains nine of the world's top ten
highest peaks and 96 of the world's 109 peaks over 24,000 feet. If the
Karakorum, Pamir, Tian Shan and Hindu Kush ranges and Tibet—which are
extensions of the Himalayas into Pakistan, China, Afghanistan and
Central Asia—are including in the Himalayas then the 66 highest
mountains in the world are in the Himalayas. The 67th highest is
Aconcagua in Argentina and Chile
Several of the greatest rivers in the world—the Ganges, Indus,
Brahmaputra, Mekong, Yangtze and Yellow rivers—originate in either the
Himalayas or the Tibetan plateau. Some people live in valleys nestled
between Himalayan ridges but few people actually live on the slopes of
the mountains. Web Sites : Wikipedia Wikipedia
Geology of the Himalayas : The Himalayas are not just one range of
mountains but a series of three parallel ranges that rise up from the
plains of India, Pakistan and Bangladesh. Between the massifs and
peaks are eroded river gorges, some of the deepest valleys in the
world, and massive, slowly-creeping glaciers.
The southernmost range, the Siwalik Hills, barely tops 5000 feet. The
Lesser Himalayas, in the middle, vary in altitude between 7,000 and
15,000 feet, and are indented with valleys like the Kathmandu Valley.
The third range is known as the Great Himalayas andthis is where all
the world'sbiggest peaks are found.
The Himalayas are young mountains. Because of this they experience
frequent landslides and rapid erosion, creating precipitous topography
with sharp peaks and V-shaped ravines rather than alluvial valleys or
lakes. Wind, rain, run off and snow continue shapingthe mountains
today. The mountains remain about the same height because the rate of
erosion is aboutthe same as the amount of uplift. The amount of
snowalso varies considerably. The greatest depths are recorded in the
summer when the monsoons dump large amounts of snow on the higher
elevation of the Himalayas. In the winter, high wind scour the
landscape and blow snow away.
Himalayas and Plate Tectonics : The Himalayas began 65 million years
when the Indian subcontinent climaxed a 70million year journey across
the Indian Ocean with a collision into Asia. The forceand pressure of
the collision between the Asianplate and India, pushed massive folds
of sedimentary rock up from out of the earth. The pressure and heat of
the mountain building forces turned some of rock into metamorphic
rocks such schists and gneisses. Wind, rain, run off and glacial ice
created the awesome Alpine shapes you see today.
Much of the rock pushed upwards by the mountain building activity is
limestone and sandstone that was once at the bottom of the ocean. It
is possible to find fossils of sea creatures in the Himalayas at an
elevation of four kilometers above sea level.
Plate tectonic continues to push the Indian subcontinent under Nepal
and China, which sit on the Eurasian Plate, forcing Tibet and the
entire Himalayan range to rise about 10 millimeters a year and move
towards China at a rate if about five centimeters a year. Before it
was pushed upwards Tibet was a well watered plain. As the Himalayas
were pushed up they deprived Tibet of rain, turning it into a dry
plateau.
The Indian Plate is moving northeastward at a rate of 1.7 inches a
year relative tothe Eurasian Plate which embraces most of Asia and
Europe.
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