The Oorsirian

Orosirian Period ran from 2.05 billion years to 1.8 billion years ago and contributed much to the development of the Earth's geological features. The name of this period suggests that there was an extensive formation of the mountains across all the continents. It can be said that it was the period of mountain formation. The Orosirian Period is dated in chronometrical order and not stratigraphically.

What are the major highlights of the Orosirian Period?

  • Extensive formation of mountains
  • Formation of the largest impact crater near Vredfort
  • Formation of the Sudbury Basin

Orosirian Period: Geological changes
As mentioned above this period is the age of formation of mountain and it is the period's major highlight. This orogeny or extensive mountain formation had taken place throughout the world irrespective of every continent of that time. The term Orogeny has a special meaning and stands for the tectonic plates' active movement. The movement was active because one of the mechanisms of formation of mountain was through the crust's lateral compression. This took place when the any two of the landmasses pushed against each other. This event also coincided with the early continent's movements like the movements of Atlantic and Ur, Nena towards each other. This event also gave birth to the rise of the first super continent of Columbia about 1.8 billion years ago.

Major impact events of the Orosirian Period
Two major impact events occurred in this period which had also enriched the features of the Proterozoic Era. Even, these two major events of the Orosirian Period still survive.
Formation of the largest impact crater near Vredefort in the Orosirian Period
It is one of the largest impact events of this period. The crater is considered as the largest impact crater, which has been formed in South Africa's Free Province and near Vredefort.
This crater was believed to have formed at the early Orosirian, about 2.023 billion years ago. It is the largest impact crater of the world and 300 km wide.

Formation of the Sadbury Basin in Canada in the Orosirian Period
It is also one the major events of the Orosirian Period. This crater was formed by the impact of an asteroid which was believed to be about 10 km in size. It is about 250 km wide and dated back to 1.85 billion years. This crater was thought to be formed during the latter or end period of the Orosirian Period. Today it is serving as one of the mineral rich areas offering large scale of mining operations for nickel and copper. These minerals have thought to be brought by the asteroid.

The Orosirian Period is not only important to assess and understand the Proterozoic Era but it is equally significant in today's world too. It acts as the major period when the Earth has undergone some of the significant changes and impacts some which are still in existence and serving the modern world. It is really interesting to explore our Earth in its varied features.