![]() At the beginning of the Indian plate’s journey, the small island of Sri Lanka was attached and located southwest of the Indian plate. The Indian plate was also rotating counterclockwise as it drifted northward. At about 55 million years ago, the northern tip of the Indian plate was crossing the equator, and about 40 million years ago it rammed into the Eurasian plate. The northward movement of the Indian plate began about 71 million years ago and the rate of movement was about 9 meters per 100 years. By about 80 million years ago, India was located approximately 6,400 kilometers south of the Eurasian plate. At this time India was a large island in very close proximity to the continental islands of Australia and Antarctica. This supercontinent had broken up and the pieces were starting to drift from each other about 200 million years ago. There were many supercontinents before Pangea, but Pangea is the last supercontinent that broke up to form today’s continents. The Indian and Eurasian PlatesĪll of today’s continental and oceanic plates started off connected as part of one big continental plate called the supercontinent Pangea. Stretching over 2,900 km along the border between the Tibetan Plateau and India, the Himalayas are evidence of plate tectonics and what happens when two continents collide. Everest, the Himalayas contain many other high peaks, making it the highest mountain range on Earth. ![]() Everest, which stands at 8,848 meters (29,029 feet) above sea level and is the highest mountain on Earth. 115-157.The Himalaya Mountains are best known for their immense peaks, such as the towering Mt. Tapponnier et al., 1986, On the mechanics of the collision between India and Asia, in Collision Tectonics, Coward & Ries (eds.): Geological Society Special Publication, no.Schelling, 1992, The tectonostratigraphy and structure of the Eastern Nepal Himalaya: Tectonics, v.Searle & Treloar, 1993, Himalayaan tectonics - an introduction: in Himalayan Tectonics, Treloar & Searle (eds.), p.Searle et al., 1987, The closing of Tethys and the tectonics of the Himalaya: Geological Society of America Bulletin, v.Molnar, 1986, The geologic history and structure of the Himalaya: American Scientist, v.Le Fort, 1996, Evolution of the Himalaya, in The Tectonics of Asia, Yin & Harrison (eds.), p.Bilham et al., 1997, GPS measurements of present-day convergence across the Nepal Himalaya: Nature, v.Allegre et al., 1984, Structure and evolution of the Himalaya-Tibet orogenic belt: Nature, v.Project INDEPTH, which has done seismic profiling across TibetĪnd the Himalaya, has an interesting, but technical, web page NASA's on-line geomorphology book describes theĪssociated geology of Afghanistan, Pakistan, western India. From north to south, these rock packages and fault zones are the Tibetan Sedimentary Sequence (blue), South Tibetan Detachment Zone (Detachment Fault), Greater Himalayan Sequence (red and pink), Main Central Thrust (MCT) and Maha Bharat Thrust (MT), Lesser Himalayan Sequence (light blue), Main Boundary Thrust (MBT) and Main Frontal Thrust (MFT), and Gangetic Basin of the Indian subcontinent (yellow). It is these zones that accommodated the huge amounts of crustal shortening as the rock sequences were slid one over another. Several distinct sequences of rock are recognized in the Himalayas, separated from one another and rocks of the Indian plate by northward-dipping fault zones. Immense slices of Indian crust were pushed southward and stacked up to produce the Himalayan orogen (above figure). This movement caused the rocks along the leading edge of the Indian plate to deform and fracture. Given the great magnitudes of the blocks of the Earth's crust involved this is a remarkable rate, about twice the speed at which your fingernails grow. The Indian plate continues to move northward relative to Asia about 5 cm per year. The collision that produced the Himalayas was only the latest, albeit climactic, episode in this long series of collisions. The resulting sutures are marked by scattered occurrences of ophiolite, ocean floor material that was caught up between theĬrustal blocks during accretion. Each older fragment, like the larger Indian Plate, made a long northward journey as the intervening ocean was subducted, and was accreted to the Eurasian continent. Paleomagnetic analysis indicates that these older microplates were in the southern hemisphere during the Paleozoic era. Were successively added to the Eurasian plate during the Paleozoic and Mesozoic eras. Tibetan Plateau itself is a collage of microplates or continental fragments that The collision between the Indian subcontinent and Eurasian continent, which started in Paleogene time and continues today, produced the Himalayas and Tibetan Plateau, spectacular modern examples of the effects of plate tectonics.
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