2.3 Earth's Layers — KEY for Diagram Labeling

2.3 Earth's Layers — KEY for Diagram Labeling

Term

Definition / Key Details

Crust

Thinnest, outermost layer. Continental (up to 70 km, less dense) and Oceanic (<10 km, denser). Where we live.

Mantle

Largest layer by volume. Solid rock that moves slowly over millions of years (like silly putty). Convection currents here drive plate tectonics.

Outer Core

Liquid iron and nickel. ITS MOVEMENT CREATES EARTH'S MAGNETIC FIELD.

Inner Core

Solid iron and nickel. Hottest layer (~5,000°C). Solid due to extreme pressure.

Tectonic Plates

Large sections of crust + upper mantle. Movement causes earthquakes, volcanoes, mountain building. Explains why continents look like puzzle pieces.

Convection

Heat transfer through fluid movement. Hot material rises, cool sinks → drives tectonic plate movement.