Geologic Formation and Structure

  The Himalayan mountain system developed in a series of stages 30 to 50 million years ago. The Himalayan range was created from powerful earth movements that occurred as the Indian plate pressed against the Eurasian continental plate.



The earth movements raised the deposits laid down in the ancient, shallow Tethys Sea (on the present site of the mountains) to form the Himalayan ranges from Pakistan eastward across northern India, and from Nepal and Bhutan to the Myanmar (Burmese) border.

Even today the mountains continue to develop and change, and earthquakes and tremors are frequent in the area

The Himalayas are known to be youngfold mountains. Young, because these have been formed relatively recently in the earth's history, compared to older mountain ranges like the Aravallis in India, and the Appalachian in the USA. They are known as fold mountains because the mountains extend for 2500 km in length in a series of parallel ridges or folds.



the continents, 180 million years ago

 Around 200 million years ago (also known as the Middle Permian Period) , an extensive sea stretched along the latitudinal area presently occupied by the Himalayas. This sea was named the Tethys. Around this period, the super continent Pangea began to gradually split into different land masses and move apart in different directions.

As a result, rivers from both the northern Eurasian land mass (called Angara) and the southern Indian land mass (called Gondwana) started depositing large amounts of sediments into the shallow sea that was the Tethys. There were marine animals called ammonites living in the sea at the time. The two land masses, the Eurasian and the Indian sub-continent, moved closer and closer. Indian plate was moving north about at the rate of about 15 cm per year (6 inches per year).

the continents, 65 million years ago

The initial mountain building process started about seventy million years ago (or the Upper Cretaceous period) when the two land masses (or plates) began to collide with each other. As a result, the already shallow seabed rapidly folded folded and was raised into longitudinal ridges and valleys.

Although the phase of major upheaval of the Himalayas has passed, the Himalayas are still rising, albeit at a much slower rate. The Indian plate is continuously moving north at the rate of about 2 cms every year. Because of this reason the Himalayas are rising at the rate of about 5 millimeter per year.

The continents today.

This means that the Himalayas are still geologically active and structurally unstable. For this reason, earthquakes are a frequent occurrence in the entire Himalayan region.