Topic: Theories (continental drift theory, sea floor spreading, plate tectonics theory)
1. What do you understand by the continental drift theory ? Discuss the evidences in support of it and also throw light on the criticism faced by it. (250 words)
Reference: Fundamentals of Physical Geography NCERT class XI
Why the question:
The question is from the static portions of GS paper I, section geography.
Key Demand of the question:
One has to elucidate upon the Continental drift theory and discuss the evidences supporting it while presenting the related criticisms.
Discuss – This is an all-encompassing directive – you have to debate on paper by going through the details of the issues concerned by examining each one of them. You have to give reasons for both for and against arguments.
Structure of the answer:
Continental Drift theory was put forth by Alfred Wegener, a German meteorologist, polar explorer, astronomer, and geologist. He is in fact known as the father of continental drift.
The answer body must discuss the following aspects –
- Continental Drift Theory (Alfred Wegener) – the concept in detail with relevant diagrams supporting it.
- The direction of drift; According to Wegener, the continents drifted in two directions: Towards the equator, towards the west. Explain these too.
- Evidence in support of the Continental Drift Theory – “Jigsaw” fit, Geological structure, Permo-carboniferous glaciations, Similar Fossil, Paleoclimatic evidence etc.
- Criticism of Continental Drift Theory – explain that the greatest criticism of this theory was due to the controversial forces which were stated to have caused the drift. Explain the other criticisms in detail.
Conclude with significance of the theory.