Question

Describe the plate motions along the Himalayan Mountains. Do you think these mountains are getting larger, smaller, or staying the same? Explain your answer.

Answer 1

Himalayas

Explanation:

• Once, all the world’s landmass was connected, forming one super-continent known as Pangea
• About 200 million years ago, tectonic forces broke apart this giant continent into pieces, eventually forming the continents that are known today
• As convection currents worked independently on the plates associated with these new continental pieces, the plates and their respective continents began to drift across the globe to their present-day geographical locations
• Eighty million years ago, India was approximately 6400 km south of the Eurasian plate, separating the two was the Tethys Sea
• The Indo-Australian tectonic plate – containing the continent of Australia, the Indian subcontinent, and surrounding ocean – was pushed northward by the convection currents generated in the inner mantle
• For millions of years, India made its way across the sea toward the Eurasian plate
• As India approached Asia, around 40 million years ago, the Tethys Sea began to shrink and its seabed slowly pushed upwards
• The Tethys Sea disappeared completely around 20 million years ago and sediments rising from its seabed formed a mountain range
• When India and Tibet collided, instead of descending with the plate, the relatively light sedimentary and metamorphic rock that makes up the subcontinent of India pushed against Tibet, forcing it upwards, and created a massive mountain fold, The Himalayas
• This process hasn’t stopped, the Indo-Australian plate is still moving toward Eurasia, still pushing Tibet upwards
• The Himalayas continue to rise by an average of 2 cm each year and the highest mountains are only getting higher