GEOLOGY

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. Outer Core The outer core, about 2, 200 kilometers (1, 367 miles) thick, is mostly composed of liquid iron and nickel.

Detailed explanation-2: -The differentiation between these layers is due to processes that took place during the early stages of Earth’s formation (ca. 4.5 billion years ago). At this time, melting would have caused denser substances to sink toward the center while less-dense materials would have migrated to the crust.

Detailed explanation-3: -Earth has a core, but this is really two distinct parts: the inner core and the outer core. Both parts of the core are made up of mostly iron and some nickel. The difference is that in the inner core, those minerals are solid and in the outer core, they’re liquid.

Detailed explanation-4: -The Earth core is clearly identified by seismic data. The indications are a clear shadow on the depth–time curves of seismic waves refracted within the mantle, compression and shear waves reflected from core’s surface, and a total decay of the shear waves within it.