SCIENCE
EARTH SCIENCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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crust
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inner core
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mantle
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outer core
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Detailed explanation-1: -The core is made of two layers: the outer core, which borders the mantle, and the inner core. The boundary separating these regions is called the Bullen discontinuity. The outer core, about 2, 200 kilometers (1, 367 miles) thick, is mostly composed of liquid iron and nickel.
Detailed explanation-2: -The outer core is the only entirely liquid layer within the Earth. It starts at a depth of 2, 890 km and extends to 5, 150 km, making it about 2, 300 km thick. In 1936, the Danish geophysicist Inge Lehmann analyzed seismic data and was the first to prove a solid inner core existed within a liquid outer core [39].
Detailed explanation-3: -Although having a composition similar to Earth’s solid inner core, the outer core remains liquid as there is not enough pressure to keep it in a solid state.