Earth's Structure and Plate Movement

Think of Earth like a massive layered cake, but one that's been in the oven for billions of years! The inner core is the hottest bit - a solid ball of iron and nickel reaching temperatures of 5500°C (hotter than the Sun's surface). Surrounding this is the outer core, which is liquid iron and nickel swirling about.

The mantle makes up most of Earth's bulk and contains the asthenosphere - a layer of semi-molten rock and magma that's crucial for plate movement. On top sits the crust, the thin rocky surface we live on, which forms part of the lithosphere along with the upper mantle.

Here's where it gets interesting: Earth's surface consists of massive slabs called tectonic plates. Continental plates are older, lighter, and virtually indestructible, whilst oceanic plates are denser and constantly being recycled. Heat from the mantle creates convection currents that push these plates around, whilst slab pull uses gravity to drag heavier oceanic plates downwards.

Quick Fact: The plates move at about the same speed your fingernails grow - roughly 2-5cm per year!