Correct Answer - Option 1 : Mohorovicic discontinuity
The internal structure of Earth refers to concentric spherical layers subdividing the Solid earth.
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It consists of an outer silicate solid crust, a highly viscous asthenosphere and solid mantle, a liquid outer core whose flow generates the Earth's magnetic field, and a solid inner core.
The Moho is the boundary between the crust and the mantle in the earth.
- This is a depth where seismic waves change velocity and there is also a change in chemical composition.
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Also termed the Mohorovicic discontinuity after the Croatian seismologist Andrija Mohorovicic (1857-1936) discovered it.
- The boundary is between 25 and 60 km deep beneath the continents and between 5 and 8 km deep beneath the ocean floor.
Hence, the correct answer is Mohorovicic discontinuity.
There are five discontinuities inside the earth:
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Conrad Discontinuity: Transition zone between SIAL and SIMA.
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Mohorovicic Discontinuity: Transition zone between the Crust and Mantle.
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Repiti Discontinuity: Transition zone between Outer mantle and Inner mantle.
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Gutenberg Discontinuity: Transition zone between Mantle and Core.
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Lehman Discontinuity: Transition zone between Outer core and Inner core.
