interior structure of the earth

• What is the outermost layer of the Earth called?

  Crust
• What layer of the Earth is beneath the crust?

  Lithosphere
• What is the layer below the lithosphere?

  Asthenosphere
• What is the uppermost part of the mantle called?

  Upper Mantle
• What is the layer between the upper mantle and the lower mantle?

  Transition Zone
• What is the layer below the transition zone?

  Lower Mantle
• What is the layer beneath the lower mantle?

  Outer Core
• What is the innermost layer of the Earth?

  Inner Core
• What is the characteristic of the Earth's crust?

  It is cold, thin, and brittle
• What are the primary rock types that make up the crust?

  Basalt and granite
• How deep is Earth's crust?

  40 km deep
• What percentage of Earth's surface does continental crust cover?

  41%
• What are the differences between continental and oceanic crust?

  • Continental Crust:
  • Less dense
  • Composed of granite
  • 30-50 km thick
  • Oceanic Crust:
  • More dense
  • Composed of basalt
  • 5-10 km thick
• What is the largest layer of the Earth?

  Mantle
• What percentage of the Earth's total volume does the mantle make up?

  84%
• What are the three regions of the mantle?

  Upper Mantle, Transition Zone, Lower Mantle
• What is the behavior of the mantle over long periods?

  Behaves like a viscous fluid
• What triggers plate tectonics?

  Slow motion of lithospheric plates
• How thick is the asthenosphere?

  180 km
• What temperature range does the asthenosphere reach?

  300-800 °C
• What is the upper mantle's highest temperature?

  900 °C
• What are the four most abundant elements in the upper mantle?

  Silicon, oxygen, magnesium, iron
• What does the transition zone do?

  Prevents large material exchanges
• How much of the Earth's volume does the lower mantle occupy?

  55%
• What is the pressure in the lower mantle?

  Up to 1.4 million times atmospheric pressure
• What is the D-Double Prime (D”) layer?

  Boundary between lower mantle and outer core
• What is the outer core primarily composed of?

  Iron and nickel
• What state is the outer core in?

  Liquid form
• What heats the outer core?

  Radioactive decay of uranium and thorium
• What temperature range does the outer core reach?

  4500 to 5500 °C
• What is the inner core primarily composed of?

  Mainly iron and nickel
• What keeps the inner core solid despite extreme temperatures?

  Immense pressure
• How is the inner core studied?

  Through seismic waves
• What do P-waves indicate about the inner core?

  It indicates its solid state
• What are the two layers of the Earth's core?

  • Outer Core:
  • Liquid iron and nickel
  • Contributes to magnetic field
  • Inner Core:
  • Solid iron and nickel
  • Extremely high pressure
• outer core is located approx. 2889-5150km below the surface
• inner core has a radius of 1220km
• inner core is found 5150km below the crust, estimated depth to center is 6371km
• D" - lowermost portion of the mantle, can be razor-thin or contain thick accumulations of iron and silicates

  - detects areas of huge melt in some areas
• lower mantle is 660-2 700km below the surface