Topic– Salient features of world’s physical geography.
1) Why was most of the Earth’s coal made all at once during the Carboniferous period? Discuss.(250 words)
Directive word
Discuss- this is an all-encompassing directive which mandates us to write in detail about the key demand of the question. we also have to discuss about the related and important aspects of the question in order to bring out a complete picture of the issue in hand.
Key demand of the question.
The question wants us to discuss as to why most of the world’s coal was formed during a particular period/ era- Carboniferous period.
Structure of the answer– write a few introductory lines about the
Body-
Discuss why most of the coal was formed during the Carboniferous period. E.g
- While coal deposits formed both before and after the Carboniferous, this period provided the mother lode. It occurred a bit over 300 million years ago.
- The evolution of the wood fiber lignin and the bark-sealing, waxy substance suberin variously opposed decay organisms so effectively that dead materials accumulated long enough to fossilise on a large scale.
- The second factor was the lower sea levels that occurred during the Carboniferous as compared to the preceding Devonian period. This promoted the development of extensive lowland swamps and forests in North America and Europe.
- During this period club mosses grow to the size of trees while insects also reached comparatively gigantic proportions due to the higher-than-modern oxygen concentration.
- The reason all that oxygen was present is the vast burial of organic material before it could be eaten by oxygen-respiring organisms.
- And while oxygen rose, atmospheric CO2 fell, eventually leading to glacial conditions. It was a massive carbon-cycle experiment that mirrored our current one but with carbon moving in the opposite direction, from the atmosphere into the ground, where it formed the coal.
- During the Carboniferous, the Pangaea supercontinent was coming together. And in a tropical swath along the equator, a mountain range (now the Appalachians) was being pushed up by continental collision.
- On either side of that growing mountain range, the crust bowed downward a bit as a result. Those ever-deepening bedrock buckets were positioned right beneath soggy tropical wetland regions etc.
Conclusion– based on your discussion, form a fair and a balanced conclusion on the given issue.