Continental Drift theory was proposed by Alfred Wegener, a geophysicist, and meteorologist in 1912. It explains how continents shift their position with time. It also explains why across different continents similar types of animals, plants, rocks, etc are found. Today the theory is redundant and is replaced by Plate tectonics theory.
Theory :
In the early 20th century, Wegener proposed that continental landmasses were “drifting” across the Earth, sometimes plowing through oceans and into each other. He called this movement continental drift.
He argued that all of Earth’s continents were once part of an enormous, single landmass called PANGAEA meaning a supercontinent, and the rest was the Mega ocean which he called PANTHALASSA meaning all water.
The PANGAEA with time drifted apart into two parts called Northern Laurasia and Southern Gondwana with Tethys sea in between. With time Northern Laurasia and Gondwana got further split into what we know as major continents on earth.
Continents that are part of Northern Laurasia were continental mass in the Northern Hemisphere that included North America, Europe, and Asia (except peninsular India).
Continents that are part of Southern Gondwana include South America, Africa, Australia, and Antarctica.
Even Today the continents are drifting. India is still moving northwards today.
When Wegner was asked what were the forces causing this drift, he mentioned two forces:
Pole fleeing force: caused due to rotation of the earth.
Tidal Force: Caused due to the gravitational pull of the moon and the sun.
The explanation of the forces was not very convincing and the scientific community went further to investigate the real cause of drifting which led to the emergence of plate tectonic theory.
Evidence of Continental Drift Theory:
1. JIG-SAW fit: If you closely observe the earth continents, you would find that every continent if rearranged together fits closely as if they were a part of a puzzle. The bulge of South America fits into the African continent. Such a fit is possible only when they were a part of a single continent initially.
2. Rocks of the same age across oceans: Through carbon dating it was found that the rocks along the brazil coast and western African coast match with each other. Marine deposits along the coast of South America and Africa are of the Jurassic age. This suggests that the ocean did not exist prior to that time.
3. TIllite: These are sedimentary rocks formed out of glacial deposits. The Gondwana system of sediments from India is known to have its counterpart in six different landmasses of the southern hemisphere.
4. Distribution of fossils: Identical species of plants and animals adapted to living on land or in freshwater are found on either side of the ocean. For eg., Mesosaurus was a small reptile adapted to shallow brackish water. The skeletons of these are found only in two localities: the southern cape province of South Africa and Iraver formations of Brazil. These two are 4800 km apart with an ocean in between. So it is obvious that both continents were adjoined once upon a time.
5. Placer Deposits: The ghana coast has no source of Gold, still we find gold deposits in Ghana. The gold-bearing veins are in Brazil and it is obvious that gold deposits of ghana are derived from the Brazil Plateau when the 2 continents lay side by side.
You can also read https://www.nationalgeographic.org/encyclopedia/continental-drift/
Hope you grabbed the core understanding of the topic, and my friends if we are adding any value to your preparation or your life would you mind doing few things for us?
Spread the word for us and review us at https://g.co/kgs/2YyKFL. Reviews help us to tell other students that this is the place they need to come to for learning and growing. Help us make a difference and we shall strive each day to add more value to your preparation. Thank you!
If you need any help let us know through an email at queries@thelaymanway.com.
You also schedule an appointment with us. We have made this chargeable because we want only serious aspirants to have a discussion with us. Thank You!
Our last blog on collision of plates: https://bit.ly/3lJzdcU
For better Understanding watch: https://bit.ly/3xzAbdX
Full courses:
Fundamentals of Physical Geography full playlist: https://bit.ly/39Xm7RH
Sign up for guidance: https://forms.gle/7mt68KmVUvYfgsbv8
Join our telegram channel: https://t.me/thelaymanway
Sign up for a FREE download of Physical Geography material: https://bit.ly/3sMvCfj Subscribe: https://bit.ly/2Y8hsa3
Economic survey and budget 2021full playlist for: https://bit.ly/2YuX6bg
How to clear UPSC prelims in5 months Playlist: https://bit.ly/3cef5L8
Government Schemes for UPSC playlist: https://bit.ly/36A2pKU
Economics for UPSC Prelims Playlist: https://bit.ly/3kgEohO
How to score 120+ In UPSC Prelims: https://bit.ly/3mE3qIL
Yearly Current Affairs Revision: https://bit.ly/3s8TckD
British Acts and Policies Playlist: https://bit.ly/3vvARQY
Environment and Ecology Series: https://bit.ly/3xhslFW
Comments