With reference to Isostasy, consider the following statements:
1. Isostasy explains the equilibrium between the Earth's crust and the denser mantle.
2. It suggests that the lithosphere behaves like a flexible shell floating on the asthenosphere.

Which of the above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Question

With reference to Isostasy, consider the following statements:
1. Isostasy explains the equilibrium between the Earth's crust and the denser mantle.
2. It suggests that the lithosphere behaves like a flexible shell floating on the asthenosphere.

Which of the above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

ONLiNE UPSC · Accepted Answer

Statement 1 is correct: Isostasy refers to the concept of gravitational equilibrium between the Earth's lithosphere (crust) and the denser, plastic mantle below it. This balance helps explain variations in Earth's topography, such as mountain heights and ocean depths.

Statement 2 is correct: Isostasy implies that the lithosphere behaves like a floating, flexible shell on the semi-fluid asthenosphere, adjusting based on weight (e.g., glaciers, sediment deposition).

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M Question 1	⏱ 0
With reference to Isostasy, consider the following statements: 1. Isostasy explains the equilibrium between the Earth's crust and the denser mantle. 2. It suggests that the lithosphere behaves like a flexible shell floating on the asthenosphere. Which of the above is/are correct? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2