How were earth's layers formed?

Answer 1

Shortly after Earth's formation and early crustal formation, an occurence called 'The Iron Catastrophe' occured, where iron sank to the center of the planet. The heat released from this occurence literally melted the entire planet, and as the iron sank to the center, lighter materials rose, the lightest forming the crust. The density of materials increases with depth. Although uranium and other heavy elements are found in the crust, it is due to their chemical preference to appear as a trace element in the silicate crust than to appear in the core.

Answer 2

Earth's layers were formed through a process called differentiation, where heavier materials sank to the center to form the core, while lighter materials floated to the surface to form the crust. This differentiation occurred early in Earth's history due to high temperatures and molten conditions, leading to the layering of the mantle, crust, outer core, and inner core that we observe today.