Question

Place the name of each layer of the earth on the top level, then put its correct description underneath the layer's name.

Answer 1

- Crust
- The thin, rigid outermost layer (5–70 km thick) made of solid rock; includes continental (granitic, thicker) and oceanic (basaltic, thinner) crust and forms Earth's surface where we live.

- Mantle
- A ~2,900 km thick layer of hot, mostly solid silicate rock rich in magnesium and iron that behaves plastically over long timescales; the upper mantle contains the ductile asthenosphere (partially molten, allows plate motion) and together with the crust the rigid lithosphere.

- Outer core
- A ~2,200 km thick layer of liquid iron–nickel alloy beneath the mantle (extends from ~2,900 km to ~5,150 km depth); its convective motion generates Earth’s magnetic field.

- Inner core
- The solid central sphere (radius ~1,220 km, from ~5,150 km to ~6,371 km depth) composed mainly of iron and nickel; extremely high pressure keeps it solid despite very high temperatures.