Olympus Mons is an enormous volcano on Mars. It is the largest ...

[Pea0909berry]

Olympus Mons is an enormous volcano on Mars. It is the largest volcano in the solar system. Compositionally and structurally, Olympus Mons is most like a shield volcano on Earth, but it is many times larger.
 
  Why should Mars produce such a monstrous shield volcano, while Earth isn't capable of producing one that large?
 
  What will be an ideal response?

Question 2

Which of the following is the least abundant natural greenhouse gas?
 
  A) oxygen
  B) nitrogen
  C) methane
  D) water vapor
  E) chlorofluorocarbons

[Jayson]

Answer to Question 1

Answer: Earth has plate tectonics. Mars does not. Shield volcanoes that erupted due to hot-spot activity on Earth got carried away from their hot-spot magma source due to the motion of the plate on which they erupted. On Mars, no such lateral motion exists, so the lava keeps piling up for the duration of the hot spot's activity.

Answer to Question 2

C