The Geology And Tectonics Of Himalayas
The Himalayas is also recognized as young-fold Mountain. Compared to the old mountains such as the Appalachian situated in USA and Aravallis in India, these mountains are young in the Earth’s History. Not only that these are also called as Fold Mountains because of their length (2500 km), which are in parallel folds and ridges. Alfred Wegener a German meteorologist developed a Theory of Continental Drift, which talked about the formation of these mountains in the year 1912. Wegener proposed that earth is made up of several massive plates called Tectonic plates.
All the continents and the oceans of the earth used to lie on these tectonic plates. At one point in time continents formed a single mass and from that single mass, continents separated from each other over a time of million of years. Around 250 million years ago, the earth had a single continent, which was known as Pangea. A single large ocean bordered this super continent. In The Middle Permian period (around 200 million years ago) the Himalayas had occupied an extensive sea, which was extended, along a latitudinal area. This extensive sea was named as the Tethys.
After the Middle Permian period the Pangea continent slowly started to split into singular landmasses and move apart from each other into different direction. As a result, the Angara River, which was from the northern Eurasian landmass, and the Gondwana, which was coming from the southern Indian landmass, started dropping large quantity of sediments in the Tethys Sea. At the time there were ammonites (marine animals) living in the Tethys Sea. The Indian Sub continent and the Eurasian, the two land masses were moving closer and closer every year.
The Indian sub continent was moving towards north at an average rate of 6 inches a year (15 cm a year). The upper Cretaceous Period, which stated around 70 million years ago, was the primary mountain building process in which both of the landmasses started to combine with each other. The shallow ocean quickly folded and elevated into longitudinal valleys and ridges. In the Upper Eocene Period which was about 65 million years ago, the second phase of mountain building started. The base of Tethys started expanding again.
The sea moved back and the base of the sea started elevating into mountain ranges. Than came another mountain period which was the Middle Miocene Period about 25 million years ago in which the Low Shivalik ranges were being formed. After the occurring of this phase of mountain building, the Indian plate pressed against the Eurasian plate and this resulted in the Himalayan Mountains to rise even further than before. This phase occurred around 600,000 years back. The major disturbance phase of the Himalayas has gone but still these mountains are rising though at a slow pace.
At a rate of 2cm a year, the Indian plate is constantly moving towards the north. This reason is making the Himalayas increase at a rate of 5mm a year. Himalayas are still geologically lively and their structure is uneven. This reason makes Earthquakes a regular incident in the region of the Himalaya. To detect the moving of the plates and elevating of Himalayas through casual examination it is virtually impossible. There is however a technology called GPS (Global Positioning System) which makes it easy to detect even the slow moving of the plates. Tectonics of the Himalayas
The Nanga Parbat part of the Himalayas is the northern side and it is situated in Pakistan. The peak rise about five kilometers beyond the old mountain base camp of the Fairy meadows. Landscapes such as these are symbols of an active tectonics. As the crust condenses in reply to the continental crash the mountain tends to grow. With the continent of India colliding with the rest of Asia, one of the greatest mountain range in the world has been produced. This provides one of the most amazing natural laboratories for understanding that how the crust bends after a continent collides with another continent.
This system is active and by the use of earthquakes, it is easier to find the outline of the movement of the Earth and transmit it to the motion of the plates. Using the history of the Indian Ocean it is easy to track the drift of the Indian continent towards the north. The Himalayas basically form three zones which are: The Himalayas, the lesser or Middle Himalayas and the Sub Himalayas which include the foothills, Tarai, Siwalik Mountain range and Duars. The Tarai and Duards peidmont are areas which lie at the base of the Himalayan mountain range. Each division shows some exact landscape features.
The Himalayas which is the highest has a vast line of snowy peak with the height being 6,100 m (20000ft). The width which is largely collected of granite is about 15 miles (25 kilometers). The Himalayas venture south towards the Middle Himalayas which is an unequal fashion. Sikkim, a state in India and Nepal region of the Himalaya has the highest peak. The snow on the peak of this part of the Himalaya diverges from 4,500 m (14,800 m) in the eastern part and in the Central area of Sikkim and Nepal and in the western area it goes to around 5,200 m (17000ft).
The Northern Himalaya has many ranges such as Kailas, Zaskar and Ladakh. On the Tibet side of the Himalayas lays the great Karakoram Range. The Himalayan region is just a few remaining inaccessible and unreachable areas in the world nowadays. High valleys in the Himalayas are used by small settlers. Cold winters and crop growing season which is very short limit the farmers to around one crop a year which is mostly barley or potatoes. These mountains have limited the trade and commerce sector despite the Karakoram highway being constructed which links Pakistan, China and Nepal.Routes which are very old and cross the mountain at a very high range are open only in the summer and have a very limited amount of trade.
• Out of This World: across the Himalayas to Forbidden Tibet by Lowell Thomas Jr. ; Grey stone Press, 1950. • Himalayas: An Aesthetic Adventure Journal article by Melissa R. Kerin; The Journal of the American Oriental Society, Vol. 124, 2004. • Mountain Geography Journal article by David Smethurst; The Geographical Review, Vol. 90, 2000. • Plate Tectonics Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2004.Sample Essay of EssayEdge