Earth science

• What are the 4 spheres/earth systems

  Atmosphere

  Biosphere

  Geosphere

  Hydrosphere
• What is the earths age?

  4.543 billion yrs. Old
• Why is atmosphere essential

  -Shield the earth from uv rays

  -maintains warmth

  -Has gases that need to support life
• What is atmosphere?

  A collective layer of gas
• What is hydrosphere

  Bodies of water
• Saline water covers the earth

  97.4%
• Fresh water

  2.6%
• Mostly covers the earth and what is the percentage

  Water, 71%
• What is biosphere?

  Where biological life resides
• What is geosphere?


  Comprises of external & internal processes
• Considered as the largest sphere

  Geosphere
• Fresh waters

  •Glacier

  •Ice caps

  •Underground reservoirs
• Mass of the earth

  5.972 x 10^24 kg
• Volume 


  1.08 x 10 ^12 km^3
• Surface area


  5.10 x 10^8 km^2
• Equatorial circumference 


  40,075 km
• Equatorial radius 


  6,356 km
• Density


  5,513 g/cm^3
• What are the 2 layer subdivision of earth

  •Composition difference

  •Physical properties
• What composes the composition difference

  •Crust

  •Mantle

  •Core
• What is crust?

  Thinnest &outermost layer
• Characteristic of continental crust

  Older & buoyant
• Continental has a thickness of

  35 km
• If the continental crust is in mountainous regionswhat us the thickness?

  70 km
• What is the density of granite in continental crust

  2.7 g/cm^3
• What are the 2 types of crust

  •Continental

  •Oceanic
• What are the characteristics of oceanic crust

  Younger & denser
• What is the thickness of the oceanic

  7km
• What is the oceanic density and what does it comprise?

  3.0 g/cm^3 of basalt and dark igneous rock
• What is the name of the boundary between crust and mantle

  Mohorovicic discontinuity
• What is mantle?


  Thickest layer
• What does the mantle comprises

  Earths volume
• What is the name of the boundary between upper and lower mantle

  Repetti discontinuity
• What is the name of the boundary between mantle and core

  Gutenberg discontinuity
• What does the core comprises

  Iron and nickel
• What is the cores density

  11 g/cm^3