Question

The Earth's interior is composed of distinct layers, each with its own unique properties and characteristics. Describe at least one characteristic of each of these layers:

Inner core
Outer core
Mantle

Answer 1

- Inner core: solid (despite very high temperature) and composed mostly of an iron–nickel alloy; extremely high pressure and density (radius ≈ 1,220 km), temperatures roughly 5,000–7,000 °C.
- Outer core: liquid iron–nickel alloy with some lighter elements; convective motion of this conducting fluid generates Earth’s magnetic field (the geodynamo); thickness ≈ 2,200–2,300 km.
- Mantle: a very thick layer (≈ 2,900 km) of silicate (rocky) material (upper mantle: olivine-rich peridotite); solid on short timescales but flows viscously over geologic time, driving plate tectonics and mantle convection.