Consider the following statement with respect to the Earth’s Crust:
Statement-I: At the convergent boundary, the oceanic crust goes beneath the continental crust.
Statement-II: Oceanic crust is thicker and denser than the Continental Crust.

Which one of the following is correct in respect of the above statements?
(a) Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I
(b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-1
(c) Statement-I is correct but Statement-II is not correcct
(d) Statement-I is not correcct but Statement-II is correct

Question

Consider the following statement with respect to the Earth&rsquo;s Crust:
Statement-I: At the convergent boundary, the oceanic crust goes beneath the continental crust.
Statement-II: Oceanic crust is thicker and denser than the Continental Crust.

Which one of the following is correct in respect of the above statements?
(a) Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I
(b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-1
(c) Statement-I is correct but Statement-II is not correcct
(d) Statement-I is not correcct but Statement-II is correct

ONLiNE UPSC · Accepted Answer

Statement I is correct: At a convergent boundary between an oceanic crust and a continental crust, the denser oceanic crust subducts (moves beneath) the lighter continental crust. This process creates a subduction zone, where the oceanic crust is pushed into the mantle and eventually melts.

Statement II is not correct: The crust is the outermost solid part of the Earth. It is brittle in nature. The thickness of the crust varies between oceanic and continental areas. Oceanic crust is thinner compared to continental crust. The average thickness of oceanic crust is 5 km, while that of continental crust is about 30 km. The continental crust is thicker in areas with major mountain systems, reaching up to 70 km thick in the Himalayan region. Oceanic crust is denser than the Continental Crust because it is mainly made up of basalt, which is denser than the granite that makes up the continental crust.

Earth's Crust

Convergent Boundaries

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M Question 1	⏱ 0
Consider the following statement with respect to the Earth’s Crust: Statement-I: At the convergent boundary, the oceanic crust goes beneath the continental crust. Statement-II: Oceanic crust is thicker and denser than the Continental Crust. Which one of the following is correct in respect of the above statements? (a) Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I (b) Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-1 (c) Statement-I is correct but Statement-II is not correcct (d) Statement-I is not correcct but Statement-II is correct