4.1.1

Structure of the Earth: Characteristics

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Structure of the Earth and Its Layers

The Earth consists of several layers: inner core, outer core, mantle, crust, and lithosphere, each with unique features affecting earthquakes and volcanoes.

Illustrative background for The inner core    Illustrative background for The inner core     ?? "content

The inner core

  • The inner core is the Earth's deepest layer.
  • The inner core is solid and mainly made of iron and nickel.
    • Its solid state affects Earth's magnetic field.
  • The inner core is extremely hot, reaching up to 5,500°C.
  • The inner core plays a crucial role in the Earth's internal heat.
Illustrative background for The outer core    Illustrative background for The outer core     ?? "content

The outer core

  • The outer core surrounds the inner core.
  • The outer core is a liquid layer made mostly of molten iron and nickel.
    • The movement of this liquid generates Earth's magnetic field.
  • The outer core's fluid nature influences tectonic activity.
    • Earthquakes and volcanoes are linked to energy from this layer.
Illustrative background for The mantle    Illustrative background for The mantle     ?? "content

The mantle

  • The mantle lies above the outer core and below the crust.
  • The mantle is semi-solid and made of silicate rocks rich in iron and magnesium.
  • The mantle is very thick, about 3000 km deep.
  • Convection currents in the mantle cause the movement of tectonic plates.
    • This movement triggers earthquakes and volcanic eruptions.
Illustrative background for The crust    Illustrative background for The crust     ?? "content

The crust

  • The crust is Earth's outermost solid layer.
  • The crust varies from 5 to 70 km thick, thinner under oceans than on continents.
  • The crust consists of rocks and minerals.
  • Tectonic plates are sections of the crust.
    • Earthquakes occur mostly in the crust due to plate movements.
Illustrative background for The lithosphere    Illustrative background for The lithosphere     ?? "content

The lithosphere

  • The lithosphere includes the crust and the upper mantle.
  • The lithosphere is rigid and broken into tectonic plates.
  • These tectonic plates float over the softer mantle below.
  • Earth's earthquakes and volcanoes mainly occur along the lithosphere plate boundaries.
    • Plate interactions form volcanoes and fault lines.

Jump to other topics

1Paper 1 - Changing River Environnments

2Paper 1 - Changing Coastal Environments

3Paper 1 - Changing Ecosystems

4Paper 1 - Tectonic Hazards

5Paper 1 - Climate Change

6Paper 2 - Changing Populations

7Paper 2 - Changing Towns & Cities

8Paper 2 - Development

9Paper 2 - Changing Economies

10Paper 2 - Resource Provision

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