UGC NET Geography 1

The north-pole lies with in the Arctic Ocean whereas south-pole is located within Antartic Continent. Which of the following theory uses this phenomenon as a supportive argument ?

(A) Theory of Isostasy

(B) Theory of Plate Tectonics

(D) Tetrahedral Theory

The answer is **(B) Theory of Plate Tectonics**.

The theory of plate tectonics states that the Earth's surface is made up of a number of large plates that are constantly moving. The North Pole lies within the Arctic Ocean because the Arctic Ocean is located on a plate that is moving away from the North Pole. The South Pole, on the other hand, is located within Antarctica because Antarctica is a continent that is not moving.

The other theories listed are not supportive of this phenomenon. The theory of isostasy states that the Earth's crust is balanced by the underlying mantle, so the North Pole would not be located in an ocean if this theory were correct. The theory of convective current theory states that the Earth's mantle is heated from below and that this heat causes the mantle to move, but this theory does not explain why the North Pole is located in an ocean and the South Pole is located on a continent. The tetrahedral theory is not a scientific theory and is not supported by evidence.

**Explanation of other theories:**

* **Theory of Isostasy** states that the Earth's crust is balanced by the underlying mantle. This means that the weight of the crust is supported by the mantle, so the crust does not sink into the mantle. The North Pole is located in an ocean because the crust in this area is relatively thin. The mantle is therefore able to push up the crust, creating an ocean.

* **Theory of Convective Current Theory** states that the Earth's mantle is heated from below and that this heat causes the mantle to move. The mantle is a layer of hot, solid rock that lies below the Earth's crust. The heat from the Earth's core causes the mantle to move in a convective current. This means that the mantle is constantly circulating, with hot material rising to the surface and cooler material sinking to the bottom. The convective current theory does not explain why the North Pole is located in an ocean and the South Pole is located on a continent.

* **Tetrahedral Theory** is not a scientific theory and is not supported by evidence. This theory states that the Earth is shaped like a tetrahedron, with the North Pole at one point of the tetrahedron and the South Pole at another point. The theory also states that the Earth's crust is made up of four plates that are constantly moving. However, there is no scientific evidence to support this theory.

Therefore, the theory of plate tectonics is the best explanation for why the North Pole lies within the Arctic Ocean and the South Pole is located within Antarctica.

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