Interpretation of a sentence

[giuly90]

Dear teachers, I cannot quite understand the second sentence of this passage:

"On the mountains, snow and ice build up into glaciers that weigh on the rocks beneath and slowly push them downhill under the force of gravity. Together with advancing ice, the rocks carve out a path as the glacier slumps down the mountain."

I wonder in particular about the meaning of "advancing ice", "carve out a path" and "slumps down th mountain".

Thank you for your help,

G.

 

[Barb_D]

The ice moves forward, and it creates a path by pushing or cutting through the rock. "Slumps" is a rather person-like way to describe the movement of the ice.