Day 14 – Q 3.Why is the African continent splitting in two unequal parts? Which geographical feature is responsible for it? What is its geographical extent? Discuss.
3. Why is the African continent splitting in two unequal parts? Which geographical feature is responsible for it? What is its geographical extent? Discuss.
अफ्रीकी महाद्वीप दो असमान हिस्सों में क्यों विभाजित हो रहा है? इसके लिए कौन सा भौगोलिक रूप जिम्मेदार है? इसकी भौगोलिक सीमा क्या है? चर्चा करें।
Introduction:
Around April, a large crack running into several Kilometers appeared in south-western Kenya. The cracks continue to grow which has raised doubt of African continent splitting into two unequal parts.
Body:
Why African continent is splitting and geographical features responsible for it:
- Plate Tectonics: The Earth’s lithosphere (formed by the crust and the upper part of the mantle) is broken up into a number of tectonic plates. These plates are not static, but move relative to each other at varying speeds, “gliding” over a viscous asthenosphere.
- Faulting and Rift Valley: When the lithosphere is subject to a horizontal extensional force it will stretch, becoming thinner. Eventually, it will rupture, leading to the formation of a rift valley.
- This process is accompanied by surface manifestations along the rift valley in the form of volcanism and seismic activity. Rifts are the initial stage of a continental break-up and, if successful, can lead to the formation of a new ocean basin.
- Convectional current in Asthenosphere: Continental rifting requires the existence of extensional forces great enough to break the lithosphere. The East African Rift is described as an active type of rift, in which the source of these stresses lies in the circulation of the underlying mantle.
- Tri-junction: In East Africa, a series of rift are bound together starting from Afar region. This rift is faulting at mean rate of 2-2.5cm/year.
Geographical extent:
- The East African Rift Valley stretches over 3,000km from the Gulf of Aden in the north towards Zimbabwe in the south, splitting the African plate into two unequal parts: The Somali and Nubian plates.
- Also along the eastern branch of the rift valley, running along Ethiopia, Kenya and Tanzania
Conclusion:
The Earth is an ever-changing planet, even though in some respects change might be almost unnoticeable to us. This change is currently happening and East African rift system is a perfect example of it.
Best Answer: Amresh Kumar
