Earth's outer core is the only layer that is completely liquid. It's primarily composed of molten iron and nickel. This layer sits beneath the mantle and extends from approximately 2,890 kilometers to 5,150 kilometers in depth.
Understanding Earth's Layers
The Earth is structured in distinct layers, each with unique properties:
- Crust: The outermost solid layer.
- Mantle: A mostly solid layer, but with some plasticity.
- Outer Core: The only completely liquid layer, crucial for Earth's magnetic field.
- Inner Core: A solid sphere, despite the high temperatures, due to immense pressure.
While other layers may contain liquid elements or exhibit fluid-like behavior under certain conditions (like the mantle's slow convection), only the outer core is entirely liquid across its extent.
Numerous scientific papers and articles discuss the Earth's layers and their composition. The liquid nature of the outer core is widely accepted and supported by various geological and geophysical evidence. For example, seismic wave studies reveal the difference in wave propagation speeds through solid and liquid materials, directly confirming the outer core's liquid state.
