GENERAL KNOWLEDGE

Detailed explanation-1: -Denser materials, like iron and nickel, sank to the core. Lighter materials, like aluminum and silicon, stayed closer to the Earth’s surface. The process in which the chemical elements separated by density is called planetary differentiation.

Detailed explanation-2: -The main heat transfer mechanism in the Earth’s mantle is convection, a thermally driven process where heating at depth causes material to expand and become less dense, causing it to rise while being replaced by complimentary cool material that sinks.

Detailed explanation-3: -What is recognized is that Earth is still differentiating into chemically distinct layers or regions. This is most evident in the processes of plate tectonics that involve ongoing production of crust at divergent plate boundaries such as the midocean ridges.

Detailed explanation-4: -The core is thus believed to largely be composed of iron, along with nickel and some lighter elements, whereas less dense elements migrated to the surface along with silicate rock.