Water is crucial to many geologic processes. Using the rock cycle ...

[itsmyluck]

Water is crucial to many geologic processes. Using the rock cycle as a guide, describe which geologic process would not happen if Earth were a waterless planet.
 
  What will be an ideal response?

Question 2

What is the evidence that the outer planets started to form before the inner planets?
 
  What will be an ideal response?

[beccamahon]

Answer to Question 1

 Some magmas would not form because water lowers their melting point so that melting can begin.
 Some forms of physical weathering, especially freeze/thaw processes, would not occur. Many forms of chemical weathering would not occur.
 Erosion involving water would not exist.
 There would be no clastic sedimentary rocks that were transported and deposited in water. Those that did exist would not have a cement that formed from an aqueous solution.
 There would be no chemical and biogenic sedimentary rocks.
 Hydrous minerals would not exist.
 Hydration and dehydration reactions would not occur during metamorphism. Many metamorphic reactions would slow down.

Answer to Question 2

The outer planets had to form before solar wind and high temperature from the Sun stripped gases from the solar system. Lower temperatures are necessary for dust particles to form by condensation. The center of the solar nebula was the hottest. The first place in the nebular disk where it would have been cool enough for condensation would be near the outside. The region where the inner planets eventually form would still be too hot.

[itsmyluck]

Correct answers!

[beccamahon]

Great! Please up vote