Final answer:
The leading edge of India began to slide under Tibet in a process known as underthrusting during the formation of the Himalayan Mountains, which was a result of the subduction process at the convergent plate boundary between the Indian and Eurasian Plates.
Step-by-step explanation:
During the formation of the Himalayan Mountains, the leading edge of India began to slide under Tibet in a process called underthrusting, which is similar to the geologic process called subduction. Subduction is the sideways and downward movement of the edge of a plate of the earth's crust into the mantle beneath another plate.
This phenomenon occurs at convergent plate boundaries, where tectonic collision between the Indian Plate and the Eurasian Plate, starting about 70 million years ago, gave rise to the highest mountain ranges in the world. The resulting pressure forces the Himalayas even higher, creating seismic activity in the region. Indeed, the large mass and height of the Himalayas continue to influence the region's culture and religion, with some mountains being considered sacred.
As the Indian plate continued to push against the Eurasian Plate, the Himalayas, which serve as a natural boundary separating India and China, were formed. This continuous tectonic activity leads not only to the rise of the mountain ranges but also to the occurrence of destructive earthquakes and tremors due to the immense geological forces at play in South Asia, a region with an intricate and long tectonic history.